Method for synthesizing epothilones and epothilone analogs

ABSTRACT

A method for making epothilones and epothilone analogs is described, as are novel compounds made by the method. Exemplary novel compounds include those according to the formula:  
                 
 
     With respect the formula, G is selected from the group consisting of  
                 
 
     R 2  substituents independently are selected from the group consisting of H and lower alkyl groups; Z is selected from the group consisting of the halogens and —CN; M is selected from the group consisting of O and NR 3 ; R 3  is selected from the group consisting of H, lower alkyl, R 4 CO, R 4 OCO, and R 4 SO 2 ; R 4  is selected from the group consisting of H, lower alkyl, and aryl; T is selected from the group consisting of CH 2 , CO, HCOH and protected derivatives thereof; W is H or OR; and X and Y independently are selected from the group consisting of O, NH, S, CO, and C. Embodiments of the method provide convenient access to analogs of the epothilones, such as those having alternate stereochemistry and those containing an ester, amide, thioester, or alkyne moieties in the macrocycle.

CROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application is a continuation-in-part of pending U.S. patentapplication Ser. No. 09/846,154, filed Apr. 30, 2001, which claims thebenefit of the earlier filing date of U.S. patent application Ser. No.09/499,596, filed Feb. 7, 2000, now abandoned, which claims the benefitof the earlier filing date U.S. Provisional Application No. 60/118,883,filed Feb. 5, 1999. Each of these prior applications is incorporatedherein by reference.

ACKNOWLEDGEMENT OF GOVERNMENT SUPPORT

[0002] The United States government may have certain rights in thistechnology pursuant to Grant No. GM-50574, awarded by the NationalInstitutes of Health.

FIELD

[0003] The present disclosure concerns a method for making epothilonesand epothilone analogs, and compounds made by the method.

BACKGROUND

[0004] I. Introduction

[0005] Epothilones A (2) and B (4) were discovered by Höfle andcoworkers while examining metabolites of the cellulose-degradingmyxobacterium Sorangium cellulosum (Myxococcales) as potentialantifungal agents. Höfle, G.; Bedorf, N.; Gerth, H.; Reichenbach (GBF),DE-B 4138042, 1993 (Chem. Abstr. 1993, 120, 52841). Höfle, G.; Bedorf,N.; Steinmeth, H.; Schomburg, D.; Gerth. H.; Reichenbach, H. Angew.Chem. Int. Ed. Engl. 1996, 35, 1567.

[0006] Although the antifungal spectrum of 2 and 4 proved to be quitenarrow, scientists at Merck found that these macrolides are highlycytotoxic. Bollag, D. M.; McQueney, P. A.; Zhu, J.; Hensens, O.; Koupal,L.; Liesch, J.; Goetz, M.; Lazarides, E.; Woods, C. M. Cancer Res. 1995,55, 2325. The epothilones had powerful activity against mouse fibroblastand leukemia cells (2 ng mL⁻¹) and strong immunosuppressive activity.Gerth, K., et al., Antibiot., 1996, 49, 560-563. By observing the effectof the epothilones on induction of tubulin polymerization tomicrotubules and noting that 2 and 4 are competitive inhibitors of Taxolwith almost identical IC₅₀ values, it was concluded that epothilones actat the cellular level by a mechanism similar to Taxol. Bollag, D. M.Exp. Opin. Invest. Drugs 1997, 6, 867; Nicolaou, et al., Angew. Chem.Int. Ed. Engl., supra. Epothilone B (2) was particularly impressive inthese assays, having a 2,000-5,000-fold higher potency than Taxol inmultiple-drugresistant cell lines. Bollag, D. M.; et al., Cancer Res.1995, supra.

[0007] After scientists from Merck reported their findings on the modeof action of epothilones in 1995, interest in these compounds increased.The Merck scientists subjected tens-of thousands of compounds tobiological assays for Taxol-like tubulin-polymerization activity.However, of the compounds assayed, only epothilones A and B provedbiologically active.

[0008] II. Tubulin and Microtubules

[0009] Tubulin polymerization-depolymerization plays an important rolein the cell cycle, particularly during mitosis. Tubulin, a heterodimerprotein comprising globular αβ-tubulin subunits is the monomericbuilding block of microtubules. Microtubules are one of the fundamentalstructural components of the cytoskeleton in all eukaryotic cells, andhelp develop and maintain the shape and structure of the cell as needed.Microtubules may operate alone, or in conjunction with other proteins toform more complex structures, such as cilia, centrioles, or flagella.Nicolaou et al., at 2019, supra.

[0010] Structurally, microtubules are regular, internetworked linearpolymers (protofilaments) of highly dynamic assemblies of heterodimersof α and β tubulin. Nicolaou et al., supra. When thirteen of theseprotofilaments are arranged parallel to a cylindrical axis theyselfassemble to form microtubes. These polymers form tubes ofapproximately 24 nm in diameter and up to several μm in length. Nicolaouet al., supra.

[0011] Growth and dissolution of microtubules are regulated by bound GTPmolecules. During polymerization, GTP molecules hydrolyze to guanosinediphosphate (GDP) and orthophosphate. The half-life of tubulin at 37° C.is nearly a full day, but that of a given microtubule may be only 10minutes. Consequently, microtubules are in a constant state of flux torespond to the needs of the cell. Microtubule growth is promoted in adividing or moving cell, but is more controlled in a stable, polarizedcell. The regulatory control is exerted by adding (for growth) orhydrolyzing (for shrinkage) GTP on the ends of the microtubule.

[0012] Microtubules are major components of the cellular apparatus andplay a crucial role in mitosis, the process during cell replication inwhich duplicated genetic material in the form of chromosomes ispartitioned equally between two daughter cells. When cells entermitosis, the cytoskeletal microtubule network (mitotic spindle) isdismantled by melting at the center, and two dipolar, spindle-shapedarrays of microtubules are formed outwardly from the centrosome.Nicolaou et al., at 2020, supra. In vertebrate cells, the centrosome isthe primary site of microtubule nucleation (microtubule-organizingcenter or MTOC). At metaphase, the dynamic action of the microtubulesassembles the chromosomes into an equatorial position on the mitoticspindle. At anaphase, the microtubule dynamics change and thechromosomes partition and move to the new spindle poles on the dynamicmicrotubules, where the new cells are being formed. Nicolaou et al.,supra. By this process, the parent cell duplicates its chromosomes,which provides each of the two daughter cells with a complete set ofgenes. When it is time for a eukaryotic cell to divide, microtubulespull its chromosomes apart and pushes them into the two emergingdaughter cells. The rate at which microtubules change their lengthincreases by 20- to 100-fold during mitosis relative to the rate duringinterphase. These rapid dynamics are sensitive to tubulin-interactiveagents that exert their antimitotic action at the metaphase-to-anaphasetransition. Kirschner et al., Cell, 1986, 45, 329-342.

[0013] III. Anticancer Drugs that Disrupt Microtubule Dynamics

[0014] A number of anticancer drugs having diverse molecular structuresare cytotoxic because they disrupt microtubule dynamics. Most of thesecompounds, including known chemotherapeutic agents colchicine, colcemid,podophyllotoxin, vinblastine, and vincristine, interfere with theformation and growth of microtubules and prevent the polymerization ofmicrotubules by diverting tubulin into other aggregates. This inhibitscell proliferation at mitosis.

[0015] Vinblastine binds to the ends of microtubules. Vinblastine'spotent cytotoxicity appears to be due to a relatively small number ofend-binding molecules. Mitchison et al, Nature, 1984, 312, 237-242.

[0016] Colchicine first binds to free tubulin to form complexes. Thesecomplexes are incorporated into the microtubules at the growth ends inrelatively low concentrations, but show profound effects on themicrotubule dynamics. Toso R. J., Biochemistry, 1993, 32, 1285-1293.

[0017] Taxol disturbs the polymerization-depolymerization dynamics ofmicrotubules in vitro by binding to the polymeric microtubules andstabilizing them against depolymerization. Cell death is the net result.Epothilones appear to act by the same mechanism and bind to the samegeneral regions as Taxol does. Bollag et al., Cancer Res., 1995, 55,2325-2333. Epothilones displace Taxol from its receptor, but bind in aslightly different manner to microtubules, as suggested by their actionagainst Taxol-resistant tumor cells, which contain mutated tubulin. Eachtubulin molecule of the microtubules contains a Taxol binding site.Taxol and epothilone binding markedly reduce the rate of α/β tubulindissociation.

[0018] Merck scientists compared the effects of the epothilones andTaxol on tubulin and microtubules and reported higher potencies for bothepothilones A and B as tubulin polymerization agents (epothiloneB>epothilone A>Taxol). All three compounds compete for the same bindingsite within their target protein. The epothilones exhibit similarkinetics in their induction of tubulin polymerization, and gave rise tomicroscopic pictures of stabilized microtubules and damaged cells thatwere essentially identical to those obtained with Taxol. Epothilones aresuperior to Taxol as killers of tumor cells, particularly multiple drugresistant (MDR) cell lines, including a number resistant to Taxol. Insome of the cytotoxicity experiments, epothilone B demonstrated a2,000-5,000-fold higher potency than Taxol, as stated above. Moreover,in vivo experiments, carried out recently at Sloan Kettering in New Yorkinvolving subcutaneous implantations of tumor tissues in mice, provedthe superiority of epothilone B.

[0019] On treatment with epothilone B, cells appear to be in disarraywith their nuclei fragmented in irregular shapes and the tubulinaggregated in distinct wedge-shaped bundles. By interacting withtubulin, the epothilones block nuclear division and kill the cell byinitiating apoptosis.

[0020] Recently, Hamel and co-workers examined the actions ofepothilones A and B with additional colon and ovarian carcinoma celllines and compared them with the action of Taxol. Kowalski R. J., etal., J. Biol. Chem., 1997, 272, 2534-2541. Pgp-overexpressing MDR coloncarcinoma lines SW620 and Taxol-resistant ovarian tumor cell line KBV-1retained susceptibility to the epothilones. With Potorous tridactyliskidney epithelial (PtK2) cells, examined by indirect immunofluorescence,epothilone B proved to be the most active, inducing extensive formationof microtubule bundles. Nicolaouet al., at 2022, supra.

[0021] Epothilone A initiates apoptosis in neuroblastoma cells just asTaxol does. Unlike Taxol, epothilone A is active against aPgp-expressing MDR neuroblastoma cell line (SK-N SH). And, the efficacyof epothilone was not diminished despite the increase of the Pgp levelduring administration of the drug.

[0022] IV. Taxol Side Effects

[0023] Taxol molecules bind to microtubules, making cell divisionimpossible, which kills the cells as they begin to divide. Since cancercells divide more frequently than healthy cells, Taxol damages tumorswhere runaway cell division occurs most profoundly. Other rapidlydividing cells, such as white blood cells and hair cells, also can beattacked. Consequently, patients taking the drug experience sideeffects. Chemotherapy with Taxol frequently is accompanied by immunesystem suppression, deadening of sensory nerves, nausea, and hair loss(neutropenia, peripheral neuropathy, and alopecia).

[0024] Taxol exhibits endotoxin-like properties by activatingmacrophages, which in turn synthesize proinflammatory cytokines andnitric oxide. Epothilone B, despite its similarities to Taxol in itseffects on microtubules, lacked any IFN-γ-treated murine-macrophagestimulatory activity as measured by nitric oxide release, nor did itinhibit nitric oxide production. Epothilone-mediated microtubulestabilization does not trigger endotoxin-signaling pathways, which maytranslate in clinical advantages for the epothilones over Taxol in termsof reduced side effects.

[0025] The importance of the epothilones as therapeutic agents recentlywas discussed on the front page of the Jan. 27, 2000, edition of theWall Street Journal. This article states:

[0026] But Taxol has its drawbacks. Some fast-dividing cancer cells canmutate into forms resistant to the drug. Often, patients with advancedcancer who respond at first to Taxol don't respond after several cyclesof treatment because their cells become resistant, too. Despiteconducting dozens of trials over the years, Bristol-Myers has beenfrustrated in its efforts to expand Taxol's effectiveness beyond certainbreast, ovarian and lung cancers.

[0027] That's why the new drugs, broadly classified as part of a familyof chemicals known as the epothilones, hold such promise. In studies notyet published, Bristol-Myers and others have shown that the epothilonesdisrupt cell division through the same biochemical pathway as Taxol. Butfor reasons scientists are only beginning to understand, the new drugsare equally effective against cancer cells already resistant to Taxol,as well as cells that develop resistance over time.

[0028] V. Syntheses of Epothilones

[0029] Based on the biological activity of the epothilones and theirpotential as antineoplastics, it will be apparent that there is a needfor an efficient method for making epothilones and epothilone analogs.Four total syntheses of 4, and several incomplete approaches, are known.See, for example: (1) Nicolaou, K. C.; Ninkovic, S.; Sarabia, F.;Vourloumis, D.; He, Y.; Vallberg, H.; Finlay, M. R. V.; Yang, Z. J. Am.Chem. Soc. 1997, 119, 7974; (2) Meng, D.; Bertinato, P.; Balog, A.; Su,D.-S.; Kamenecka, T.; Sorensen, E. J.; Danishefsky, S. J. J. Am. Chem.Soc. 1997, 119, 10073; (3) May, S. A.; Grieco, P. Chem. Commun. 1998,1597; (4) Schinzer, D.; Bauer, A.; Schieber, J. Synlett 1998, 861; (5)Mulzer, J.; Mantoulidis, A. Tetrahedron Lett. 1996, 37, 9179; (6) Claus,E.; Pahl, A.; Jones, P. G.; Meyer, H. M.; Kalesse, M. Tetrahedron Lett.1997, 38, 1359; (7) Gabriel, T.; Wessjohann, L. Tetrahedron Lett. 1997,38, 1363; (8) Taylor, R. E.; Haley, J. D. Tetrahedron Lett. 1997, 38,2061; (9) Brabander, J. D.; Rosset, S.; Bemardinelli, G. Synlett 1997,824; (10) Chakraborty, J. K.; Dutta, S. Tetrahedron Lett. 1998, 39, 101;(11) Liu, Z.-Y.; Yu, C.-Z.; Yang, J. D. Synlett 1997, 1383; (12) Liu,Z.-Y.; Yu, C.-Z; Wang, R.-F.; Li, G. Tetrahedron Lett. 1998, 39, 5261;(13) Mulzer, J.; Mantoulidis, A.; Öhler, E. Tetrahedron Lett. 1997, 38,7725; and (13) Bijoy, P.; Avery, M. A. Tetrahedron Lett. 1998, 39 1209.

[0030] Methods for making epothilone and epothilone analogs also havebeen described in the patent literature, including: (1) Schinzer et al.,WO 98/08849, entitled “Method for Producing Epothilones, andIntermediate Products Obtained During the Production Process”; and (2)Reichanbach et al., WO 98/22461, entitled “Epothilone C, D, E, and F,Production Process, and Their Use as Cytostatic as well as PhytosanitaryAgents.” One disadvantage associated with these prior processes forsynthesizing epothilones is the lack of stereoselectivity in theproduction of the Z trisubstituted bond of the desepoxyepothilone. As aresult, a new synthetic approach to epothilones and epothilone analogsis required which addresses this and other problems associated withsyntheses of the epothilones known prior to the present disclosure.

SUMMARY

[0031] The present disclosure provides a novel method for makingepothilones and epothilone analogs. The method can provide almostcomplete stereoselectivity with respect to producing the Ztrisubstituted double bond of the desepoxyepothilone, and thereforeaddresses one of the disadvantages associated with methods known priorto the present disclosure.

[0032] One embodiment of the present disclosure provides compoundshaving the structure represented by Formula 1.

[0033] With respect to Formula 1, G is selected from the groupconsisting of

[0034] R substituents independently are H, lower alkyl, or a protectinggroup, such as a silyl group; R₁ is an aryl group, such as comprising abenzene derivative, or a heterocyclic aryl group, such as a thiazolederivative. R₂ substituents independently are selected from the groupconsisting of H and lower alkyl groups; Z is selected from the groupconsisting of the halogens and —CN; M is selected from the groupconsisting of O and NR₃; R₃ is selected from the group consisting of H,lower alkyl, R₄CO, R₄OCO, and R₄SO₂; R₄ is selected from the groupconsisting of H, lower alkyl, and aryl; T is selected from the groupconsisting of CH₂, CO, HCOH and protected derivatives thereof; W is H orOR; and X and Y independently are selected from the group consisting ofO, NH, S, CO, and C.

[0035] In certain disclosed embodiments X and Y define a carboxylic acidderivative, such as provided by an ester, thioester, or amide bond. Oneexample, without limitation of such an ester bond is formed where X isC═O and Y is O. In other preferred embodiments X and Y mutually comprisea triple bond.

[0036] In particular preferred embodiments, R₁ is a group according toFormula 2 where X and Y independently are selected from the groupconsisting of O, N, and S, and R₆ is selected from the group consistingof H and lower alkyl. A particular class of aryl group according toFormula 2 is the thiazole class.

[0037] A method for synthesizing compounds according to Formula 1 isprovided. One embodiment of the method comprises providing a compoundaccording to Formula 3.

[0038] Compounds according to Formula 3 are subjected tomacrolactonization conditions to yield macrocyclic compounds accordingto Formula 1.

[0039] Another embodiment of the method comprises procedures forsynthesizing compounds according to Formula 3. One embodiment of suchprocedures comprises providing a compound according to Formula 4, and acompound according to Formula 5, and coupling the compounds to form abond between X and Y, thereby yielding a compound

[0040] according to Formula 3. In particular embodiments, coupling thecompounds comprises reacting compounds having Formulas 4 and 5 by areaction selected from the group consisting of organometallic reactions,such as transition metal-mediated coupling reactions, and amidebond-forming reactions, esterification reactions, thioesterificationreactions, and the like.

[0041] One embodiment of the method comprises first providing a compoundhaving Formula 6.

[0042] With reference to Formula 6, R is H or a protecting group; R₁ isan aryl group, such as, without limitation, benzene derivatives or thethiazole of epothilone B; R₂-R₅ substituents independently are selectedfrom the group consisting of H and lower alkyl groups; and R₆,substituents independently are selected from the group consisting of Hand lower alkyl groups. Compounds having Formula 6 are then convertedinto an epothilone or an epothilone analog. For example, in thesynthesis of epothilone B the step of converting the compound caninvolve first removing the protecting groups, and thereafter forming anepoxide at C12-C13.

[0043] In preferred embodiments, R₁ is the thiazole shown below.

[0044] Most known epothilones have this thiazole derivative as the arylgroup.

[0045] Providing compounds having Formula 6 can be accomplished in anumber of ways. One embodiment comprises coupling a first compoundhaving Formula 7,

[0046] where R is H or a protecting group and X is a functional group orchemical moiety equivalent to a carbanion at a terminal carbon of thefirst compound, with a second compound having Formula 8. With referenceto Formula 8, R₆ substituents independently are selected from the groupconsisting of H and lower alkyl groups, R is H or a protecting group,and Y is an electrophilic group capable of reacting with and coupling tothe terminal carbon of the first compound, for example, Y can be analdehyde. The precursor compound is then converted into compounds havingFormula 6. For example, two compounds, one having Formula 7 and theother Formula 8, can be coupled by a Wittig reaction where X is PPH₃+and Y is a carbonyl compound, such as an aldehyde.

[0047] Compounds having Formula 6 can be provided by a second embodimentof the disclosed method. This second embodiment involves coupling afirst compound having Formula 9

[0048] where R is H or a protecting group and X is a halide, with asecond compound including an alkyne and having Formula 10.

[0049] With reference to Formula 10, R groups independently are H, aprotecting group, or a lower alkyl group. This compound is thenconverted into a compound having Formula 6. This embodiment can proceedby first forming an enyne precursor compound having Formula 11 where thesubstituents are as stated above.

[0050] Thus, another embodiment of the present method for formingepothilones or epothilone analogs comprises forming the precursor enynecompound having Formula 11 where R₁ is H or a protecting group, or is athiazole group according to the triene compound having Formula 12 whereR groups independently are H, a protecting group, or a lower alkylgroup. Compounds having Formulas 11 and/or 12 are then converted into acompound having Formula 13, where

[0051] the carbon atom numbers correspond to the numbering system statedfor epothilone A.

[0052] With reference to Formula 13, R—R₇ are independently selectedfrom the group consisting of H, lower aliphatic groups, particularlylower alkyl groups, protecting groups, or are bonded to an 0 in anepoxide or N in an aziridine. More particularly, R substituentsindependently are H, lower alkyl, or a protecting group; R₁ is an arylgroup; R₂ is H or lower alkyl; C13 and C12 are carbons bonded togetherby a single bond or a double bond; R₃ and R₄ independently are H, loweraliphatic groups, or are bonded to 0 in an epoxide or to N in anaziridine; C10 and C9 are carbons in a double bond or triple bond, and,where C10 and C9 are carbons in a double bond, R5 and R6 independentlyare H, or lower aliphatic; and R7 substituents independently areselected from the group consisting of lower aliphatic groups. Theconfiguration of the double bond between C10 and C9 may be cis or trans,i.e., E or Z. Compounds having Formula 13 are then converted into anepothilone or an epothilone analog.

[0053] Moreover, a compound having Formula 11 may be converted into acompound having Formula 12, such as by catalytic semi-hydrogenation.Lindlar's catalyst has proved to be an effective catalyst for conductingthis catalytic semi-hydrogenation.

[0054] The disclosed embodiments of the present method differ from knownsynthetic pathways in a number of ways, such as by assembling themacrolide from two segments, which first are connected at C9-C10 beforemacrolactonization. With reference to the first disclosed embodiment ofthe present method, fragments were constructed around a preformed Ztrisubstituted alkene to circumvent stereochemical problems afflictingknown synthetic methods. The 9,10 olefin produced by coupling the twosegments confers rigidity on the one portion of the epothilonemacrocycle that exhibits flexibility, and hence may be expected toaffect its tubulin binding properties. Moreover, this alkene provides achemical moiety from which novel epothilone analogs can be prepared.

[0055] Epothilones, such as epothilone A, epothilone B, epothilone C,epothilone D, epothilone E, and epothilone F, can be made by the presentmethod. The disclosed method also provides access to novel compounds.These compounds typically have Formula 13

[0056] where the substituents are as described above. Preferredcompounds satisfying Formula 13 include one or more of the following:(1) R being hydrogen; (2) R₁ being the aryl thiazole side chain of theepothilones; (3) R₂ being hydrogen or methyl; (4) R₃-R₆ being hydrogenor methyl, or R₃ and R₄ and/or R₅ and R₆ being bonded to oxygen in anepoxide; (5) R7 being lower alkyl, particularly methyl.

[0057] Compounds having Formula 13 include several chiral centers, whichallows for a plurality of diastereomers. The disclosed method isdirected to all such stereoisomers.

[0058] However, naturally occurring epothilones have knownstereochemistries at each of the chiral centers. As a result, preferredcompounds have the same stereochemistries at each chiral center, as dothe epothilones. This is illustrated below in Formula 14, which showsthe stereochemistries of preferred epothilone analogs at certain chiralcenters. With respect to Formula 14, certain centers are representedstereoambiguously; however, the present method provides access tocompounds having defined stereochemistry at these positions. Thus, incertain embodiments of the present method, compounds having controlledstereochemistry at positions 4, 9, 10, 12, 13 and 15 can be prepared.

[0059] The present disclosure describes novel, biologically activeepothilone analogs having the general structure represented by Formula15. With reference to Formula 15, particular embodiments includecompounds wherein R is H or a protecting group; R₁ is an aryl group,such as, without limitation, benzene derivatives, the thiazolederivative of epothilone B; R₂ and R₃ substituents are selectedindependently from the group consisting of H and lower alkyl groups; andR₄ substituents are selected independently from the group consisting oflower alkyl groups. Group Y at position 9 can comprise a heteroatom,such as an oxygen, nitrogen, or sulfur. In particular embodiments, Y isan oxygen atom, such as in an ester bond with a carbonyl at position 10of an epothilone analog. Likewise, Y can comprise an NH group in an

[0060] amide bond or a sulfur in a thioester linkage. Group X atposition 10 can comprise a carbon, such as a methylene, a methine, or acarbon bonded to a heteroatom, such as an oxygen atom. In particularembodiments, group X is a carbonyl, such as a carboxylic acidderivative. For example X can be bonded to Y in an ester, thioester oramide linkage.

[0061] The present method provides novel synthetic routes to compoundshaving the general structure represented by Formula 15. For example,with reference to Formula 16, Y can be a hydroxyl group, and as such,can be oxidized to provide the corresponding carboxylic acid. Thiscompound can then be coupled, for example, with a compound having thestructure represented by Formula 17.

[0062] With reference to Formulas 16 and 17, each R group independentlycan be H or a protecting group, with R₁-R₄ as defined above. Inparticular embodiments, groups X and Y independently comprise an oxygen,nitrogen or sulfur, such as in an alkoxy group, an amine, or asulfhydryl, respectively.

DETAILED DESCRIPTION

[0063] The process of the present method can be used to make knownepothilones A, B, C, D, E and F, as well as analogs of these compounds,including the cryptothilones, which typically are dilactone orlactone-amide-type analogs of the epothilones. The cryptothilones arehybrid structures that include a portion of cryptophycins and a portionof the epothilones. One such novel diene analog 10 has double bonds atpositions C9-C10, and C12-C13. The

[0064] alkene configurations at C₉-C10, and C12-C13 can be cis or trans(Z or E), including compounds 11 and 12.

[0065] Using compound 10 and/or 11 to make analogs of epothilones, suchas the cryptothilones, provides advantages relative to prior knownsyntheses, as indicated above.

[0066] A method for making diene 10 and converting 10 into, for example,epothilone B, as well as other epothilones and epothilone analogs, isdescribed below.

[0067] I. Epothilone Structures and Epothilone Analogs

[0068] Formula 1 is a generic structural formula for diene and enynederivatives of Compound 10, and analogs of the epothilones, such as abislactone analog.

[0069] Preferred compounds have the stereochemistries shown in Formula14.

[0070] With reference to Formula 14, R is H, lower aliphatic, preferablylower alkyl, or a protecting group; R₁ is an aryl group; C13 and C12 arecarbons bonded together by a single or double bond; R₃ and R₄independently are H, lower alkyl, or are bonded to oxygen in an epoxideor to nitrogen in an aziridine; C10 and C9 are carbons in a single bond,double bond or triple bond, with preferred compounds having C10 and C9bonded together by a double bond or a triple bond; if C10 and C9 arebonded together by a double bond, the configuration of the double bondmay be cis or trans or E or Z; and R₅ and R₆ independently are H, loweraliphatic, preferably lower alkyl, or are bonded to heteroatoms incyclic structures, such as to oxygen in an epoxide or to nitrogen in anaziridine.

[0071] As used herein, “lower” refers to carbon chains having 10 orfewer carbon atoms, typically less than 5 carbon atoms. “Loweraliphatic” includes carbon chains having: (a) sites of unsaturation,e.g., alkenyl and alkynyl structures; (b) non-carbon atoms, particularlyheteroatoms, such as oxygen and nitrogen; and (c) all branched-chainderivatives and stereoisomers.

[0072] The phrase “protecting group” is known to those of ordinary skillin the art of chemical synthesis. “Protecting group” refers generally toa chemical compound that easily and efficiently couples to a functionalgroup, and can be easily and efficiently removed to regenerate theoriginal functional group. By coupling a protecting group to a firstfunctional group of a compound other functional groups can undergochemical or stereochemical transformation without affecting thechemistry and/or stereochemistry of the first functional group. Manyprotecting groups are known and most are designed to be coupled to onlyone or a limited number of functional groups, or are used for particularcircumstances, such as reaction conditions. Theodora Greene's ProtectingGroups in Organic Syntheses, (Wiley Science, 1984), and later editions,all of which are incorporated herein by reference, discuss protectinggroups commonly used in organic syntheses. Examples of protecting groupsused to protect hydroxyl functional groups for the syntheses ofepothilones and epothilone analogs include the silyl ethers, such ast-butyl dimethyl silyl (TBDMS) ethers, and tetrahydropyranyl (THP)ethers.

[0073] The term “analog” refers to a molecule that differs in chemicalstructure from a parent compound, for example a homolog (differing by anincrement in the chemical structure, such as a difference in the lengthof an alkyl chain), a molecular fragment, a structure that differs byone or more functional groups, or an ion differing in ionization statefrom the parent compound.

[0074] A “derivative” is a chemical substance structurally related to aparent substance and theoretically derivable from it.

[0075] “R groups” in generic structural formulas are typically recitedas being independent. This means that each R group can be varied, onefrom another, even when designated with the same R group. Thus each Rgroup can represent the same chemical moiety, some R groups can be thesame chemical moiety, or each R group can represent a different chemicalmoiety.

[0076] “Aryl” refers to compounds derived from compounds having aromaticproperties, such as benzene. “Aryl” as used herein also includescompounds derived from heteroaromatic compounds, such as oxazoles,imidazoles, and thiazoles.

[0077] Preferred aryl groups have Formula 2

[0078] where X and Y are independently selected from the groupconsisting of heteroatoms, particularly oxygen, nitrogen and sulfur, andR₆ is selected from the group consisting of lower alkyl. For theepothilones, and most epothilone analogs, the R₁ aryl group is thiazole18 shown below.

[0079] C12 and C13 of Formula 13 are carbons bonded together by a singleor double bond. Whether C12 and C13 are joined by a single or doublebond determines, in part, substituents R₃ and R₄. For example, if C12and C13 are coupled by a single bond, then R₃ and R₄ independently areselected from the group consisting of hydrogen and lower alkyl.Moreover, if C12 and C13 are coupled by a single bond then R₃ and R₄ canbe bonded to a heteroatom, such as oxygen and nitrogen, in a cyclicstructure, such as an epoxide or an aziridine. Epoxide 20 and aziridine22 are examples of these compounds.

[0080] Several chiral centers of these structures are representedstereoambiguously to indicate that the various stereoisomers are withinthe scope of the disclosed method. With respect to the aziridineanalogs, such as aziridine 22, R₂ is selected from the group consistingof hydrogen, lower aliphatic, particularly lower alkyl, acyl, and aryl.Preferred compounds have R₂ be hydrogen or lower alkyl.

[0081] C9 and C10 of Formula 13 are carbons bonded together by a single,double or triple bond. Whether C9 and C10 are joined by a single bond, adouble bond or a triple bond determines, in part, substituents R₅ andR₆. For example, if C9 and C10 are coupled by a single bond, then R₅ andR₆ typically are selected from the group consisting of hydrogen andlower aliphatic, preferably lower alkyl. Moreover, if C9 and C10 arecoupled by a single bond then R₅ and R₆ also can be bonded to aheteroatom, such as oxygen and nitrogen, in a cyclic structure, such asan epoxide or an aziridine. Epoxide 24 and aziridine 25 provide examplesof these compounds.

[0082] Compounds 26-35 provide additional examples of epoxide/aziridineepothilone analogs.

[0083] II. Biological Activity

[0084] Known epothilones have significant biological activity. Novelepothilone analogs made according to the method also have been shown tohave significant biological activity. For example, Tables 1 and 2provide biological data for certain epothilones and epothilone analogs.The antiproliferative activity of cis 9,10-dehydroepothilone D and trans9,10-dehydroepothilone D was assessed in vitro using a panel of humancancer cell lines.

[0085] As illustrated in Table 1, cis 9,10-dehydroepothilone was 20- to30-fold less potent than natural epothilone D, and 330- to 670-fold lesspotent than epothilone B. Interestingly, trans 9,10-dehydroepothilone Dshowed biological activity very similar to that of its cis isomer inspite of an apparent difference in the conformation of these twomacrolactones. Thus, the average IC₅₀ of trans 9,10-dehydroepothilone Dfor growth inhibition in the cell line panel used in this study was only1.36-fold higher than that observed for cis 9,10-dehydroepothilone D. Asnoted for epothilones B and D, cis 9,10-dehydroepothilone D and trans9,10-dehydroepothilone D retain full anti-proliferative activity againstKB-8511 cells, a paclitaxel-resistant cell line overexpressingP-glycoprotein (Table 1). While the tubulin polymerization activity ofcis 9,10-dehydroepothilone D and trans 9,10-dehydroepothilone D waslower than of natural epothilone D (56%, 36%, and 88%, respectively)(Table 1), it is conceivable that decreased cellular penetration maycontribute to the reduction in antiproliferative potency observed forcis 9,10-dehydroepothilone D and trans 9,10-dehydroepothilone D. Theabsence of a clear difference in the biological profiles of cis andtrans analogs of 9,10-dehydroepothilone D observed here has a parallelin results previously reported for other epothilone analogs. Thus,epothilones incorporating a trans epoxide or trans olefin at C12-C13have been shown to possess biological activity comparable to their cisisomer. TABLE 1 IC₅₀ IC₅₀ KB-31 KB-8511 IC₅₀ IC₅₀ IC₅₀ IC₅₀ Tubulin(Epider- (Epider- A549 HCT-116 PC3-M MCF-7 Compound Polym.^(a) moid)^(b)moid)^(b,c) (lung)^(b) (colon)^(b) (prostate)^(b) (breast)^(b)

95 0.17 0.16 0.16 0.34 0.32 0.29 Epothilone B

88 1.94 1.00 4.62 4.48 7.40 2.31 Epothilone D

56 59.39 28.54 109.03 101.83 146.47 72.00 9,10-cis- Dehydroepothilone D

36 103.70 70.37 109.27 109.97 146.80 95.03 trans 9,10-, trans 12,13-Dehydroepothilone D Paclitaxel (Taxol) 53 2.67 841.80 5.19 4.88 6.623.26

[0086] With reference to Table 2, the bislactone epothilone analog wastested as indicated under the conditions used for Table 1. Thebislactone was standardized against epothilone B, epothilone D, andpaclitaxel in each experiment. The data indicate that although thebislactone is less active than epothilone B and D, the analog retainsuseful biological activity, particularly against the paclitaxelresistant KB-8511 cells. TABLE 2 Tubulin IC₅₀ KB-31 IC₅₀ KB-8511Compound Polym. (Epidermoid) (Epidermoid)

21.4 25.5 25.2 Bislactone

81.4 0.24 0.15 Epothilone B

62.3 1.94 1.00 Epothilone D Paclitaxel 38.9 2.9 661

[0087] Taken together, these data support the proposition that theC₈-C₁₃ region of the epothilone perimeter is relatively tolerant ofstructural modification and suggest that the interaction of this segmentof the molecule with tubulin is less stringently defined.

[0088] III. Method for Making Epothilones

[0089] The synthesis of epothilones can be exemplified by a workingembodiment of a method for making epothilone B. Epothilone B wassynthesized by coupling a first subunit with a second subunit to form acoupled intermediate for forming epothilones. One embodiment of themethod comprised coupling a first subunit 36 with a second subunit 38.

[0090] A second embodiment comprised coupling a first allylic halidesubunit 40 with a second alkyne subunit 42. With respect to 36, 38, 40,and 42, the R substituents are as described above.

[0091] A first embodiment of a the present method for making epothilonesand epothilone analogs comprised making a suitable subunit 36 asillustrated by Scheme 1, i.e., compound 60.

[0092] Synthesis of segment 36, as represented by 60 in Scheme 1, beganfrom (Z)-3-iodo-2-methyl-2-propen-1-ol prepared in geometrically pureform from propargyl alcohol. After protection to provide 44, theiodoalkene was converted to the corresponding cuprate, which underwentclean conjugate addition to (S)-3-acryloyl-4-benzyl-2-oxazolidinone (45,not shown) to yield 46. Hydroxylation of the sodium enolate derived from46 with Davis oxaziridine gave 48. See, for example, Evans et al. Angew.Chem. Int. Ed Engl. 1997, 26, 2117. The configuration of 48 wasconfirmed by oxidative degradation to dimethyl (S)-malate. Protection ofalcohol 48 as silyl ether 50, followed by exposure to catalyticpotassium thioethoxide in ethanethiol provided 52, along with recoveredoxazolidinone (93%). Treatment of thioester 52 with lithiumdimethylcuprate furnished ketone 54, which upon Homer-Emmonscondensation with phosphonate 53 (shown below) produced diene 56 inexcellent yield, accompanied by 5% of its (4Z) isomer.

[0093] The tetrahydropyranyl ether protecting group was removed usingmagnesium bromide. The liberated alcohol was converted to bromide 58.Homologation of 58 to phosphonium bromide 60 usingtriphenylmethylenephosphorane completed the synthesis of segment 36, asrepresented by compound 60 in Scheme 1.

[0094] One embodiment of a segment 38, i.e., compound 74, was made asillustrated by Scheme 2. A key construction in one embodiment of asuitable segment 38 involved an aldol condensation of ketone 62 withaldehyde 64. This double stereodifferentiating reaction proceeded ingood yield to give anti-Felkin product 66 as the sole stereoisomer. Animportant contribution to the stereoselectivity of this condensation ismade by the p-methoxybenzyl (PMB) ether of 64, since the TBS protectedversion of this aldehyde resulted only in a 3:2 mixture of 66 and itsFelkin diastereomer, respectively. The favorable outcome with 64 isconsistent with chelation of the aldehyde carboxyl with both the lithiumenolate from 62 and the PMB ether. After protection of 66 as tris ether68, the terminal olefin was cleaved oxidatively to carboxylic acid 70,which was converted to its methyl ester 72. Hydrogenolysis of the PMBether and oxidation of the resultant alcohol 74 yielded aldehyde 76.

[0095] Subunits 60 and 76 were coupled together, followed bymacrolactonization, to provide the diene lactone precursor to epothiloneB as shown below in Scheme 3. Wittig coupling of the ylide from 58,compound 60, with aldehyde 76 at low temperature afforded triene 78 as asingle stereoisomer in excellent yield. Selective removal of the C15silyl ether of 78 was unsuccessful. But, after saponification tocarboxylic acid 80 this deprotection was readily accomplished withtetra-n-butylammonium fluoride. Macrolactonization of seco acid 82 wascarried out under Yamaguchi's conditions and both silyl ethers werecleaved with acid to yield 9,10-dehydrodes-epoxyepothilone B 84.

[0096] Compounds made in this manner can be converted to epothilonesusing conventional chemistry. For example, selective hydrogenation ofthe disubstituted olefin of 84 with diimide gave the known lactone 86.Lactone 86 underwent epoxidation with dimethyldioxirane to produce 4.Epoxidation of lactone 86 to provide epothilone B (4) can beaccomplished according to the method of Danishefsky et al., Angew. Chem.Int. Ed. Engl., 1997, 36, 757, which is incorporated herein byreference. Characterization data for both 86 and 4 matched those in theliterature and/or of the naturally occurring product. The ¹H NMRspectrum of 4 was in excellent agreement with that provided by ProfessorGrieco.

[0097] Schemes 1-3 provide a convergent synthesis of epothilone B (4),which generates all seven of its asymmetric centers in a completelystereoselective fashion. In addition, clean Z configuration at theC12-C13 double bond is incorporated by this pathway. Finally, the Zolefin at C9-C10 provides a chemical moiety from which exploratorystructural modifications can be made.

[0098] Scheme 4 illustrates a second embodiment of a method for makingepothilones and epothilone analogs. With reference to Scheme 4, compound76 was made as illustrated above in Scheme 2, and as discussed in moredetail in Example 16. Aldehyde 76 was reacted with dimethyldiazophosphonate [J. C. Gilbert et al., J. Org. Chem. 1982, 47, 1837] inTHF at −78° C. to provide alkyne 88 in approximately 80% yield. Thecopper (I) derivative of alkyne 88 was produced and was found to couplewith allylic halide 58. This reaction was extensively investigated, andwas found to proceed to product 90 best when the conditions for thereaction were as shown in Table 3, using about 5% CuI, Et₃N, Et₂O-DMF,and about 2.0 equivalents of 88. Conditions investigated for thiscoupling are summarized below in Table 3. TABLE 3 Equivalents Reagents/of 88 Coupled With Conditions Product Yield 1.1 Allylic Bromide 58 5%CuI, TBAB, K₂CO₃, DMF 8 1.1 Allylic Bromide 58 20% CuI, ALIQUOT 336, 11K₂CO₃, DMF 1.1 Allylic Bromide 58 50% CuI, Pyrrolidine, DMF 0 1.1Allylic mesylate 58B (a) Ms₂O, Et₃N, DMF 34 (b) 10% CuI, Na₂CO₃, TBAB,DMF 1.1 Allylic mesylate 58B (a) Ms₂O, Et₃N, CH₂Cl₂ 42 (b) 20% CuI,Na₂CO₃, TBAB, DMF 1.1 Allylic Chloride 58A 5% CuI, Et₃N, Et₂O-DMF 24 2.0Allylic Chloride 58A 5% CuI, Et₃N, Et₂O-DMF 60

[0099] Product 90 was semi-hydrogenated over Lindlar's catalyst[Pd/CaCO₃, Pd(OAc)₂]. This reaction was found to proceed best whenhexanes was used as the solvent. The hydrogenated product was thensaponified using NaOH and isopropyl alcohol at 45° C. to provide thecorresponding seco acid 80 in approximately 66% yield. The C15 TBS ether80 was then deprotected using TBAF and THF by warming the reaction from0° C. to 25° C., with a yield of about 89%. The selectivity of thisreaction is attributed to sterically favorable transilyation involvingthe carboxylate anion. The resultant silyl ester is hydrolyzed duringaqueous work-up. Macrolactonization was then performed under Yamaguchiconditions. Yamaguchi et al., Bull Chem. Soc. Jpn. 1970, 52, 1989. Theremaining TBS ether protecting groups were then removed usingtrifluoroacetic acid (TFA) in dichloromethane at 0° C. to providecompound 84. Compound 84 was then converted to 4 as discussed withrespect to Scheme 3 and Examples 21, 22 and 23.

[0100] Schemes 5, 6, and 7 illustrate an embodiment of a synthesis viaStille coupling that yields epothilone derivatives containing a trans(or E) double bond between C9 and C10 (See Formula 13).

[0101] With reference to Scheme 5, compound 92 was esterified with2-(trimethylsilyl)ethanol using Mitsunobu conditions to provide 94.Hydrogenolysis removed the p-methoxybenzyl ether from 94, and oxidationof alcohol 95 afforded an aldehyde, which was reacted with Bestmann'sreagent (Miller et al. Synlett. 1996, 521) to give terminal alkyne 96.Hydrostannylation of the latter in the presence of a palladiumdichloride catalyst furnished vinylstannane 98

[0102] With reference to Scheme 6, compound 48, which was prepared fromcompound 46 of Scheme 1, was protected as TES ether 49 by reaction withtriethylsilyl triflate. The latter was advanced to alcohol 104 by afour-step sequence analogous to that used for converting 48 to 56 (seeScheme 1) and including a final step of removing the tetrahydropyranylether protecting group with magnesium bromide. For Stille couplingpurposes, the allylic chloride 106 (prepared by chloride displacement ofthe corresponding mesylate prepared from compound 104) was found to bemore effective than the corresponding bromide (Scheme 1). Coupling of 98with 106 (Scheme 7) in the presence of catalytic dipalladiumtris(dibenzylideneacetone)chloroform complex and triphenylarsine (Farinaand Krishnan, J. Am. Chem. Soc. 1991, 113, 9585) proceeded in high yieldand gave the 9E,12E,16E-heptadecanoate 108. Exposure of 108 totetra-n-butylammonium fluoride cleaved both the (trimethylsilyl)ethylester and the triethylsilyl ether but left tert-butyldimethylsilylethers at C3 and C7 intact. The resulting seco acid 110 underwent facilemacrolactonization to 112 under Yamaguchi conditions. Subsequent removalof the remaining pair of TBS ethers with trifluoroacetic acid furnishedtrans 9,10, trans 12,13-dehydroepothilone D (114).

[0103] Scheme 8 illustrates an embodiment of the method that provides aconformationally constrained epothilone analog, 9,10-didehydroepothiloneD (124). Compound 124 was synthesized, its conformation studied, and itstubulin polymerization and antiproliferative activity assayed by Whiteet al. Org. Lett. 2002, 4, 995997, which is incorporated herein byreference.

[0104] With reference to Scheme 8, allylic chloride 106 (Scheme 6) wascoupled with alkyne 116 in the presence of cuprous iodide to afforddienyne 118. This dienyne was treated with TBAF to effect selectivedeprotection of the TES and TMSE blocking groups, yielding compound 120.The resulting hydroxy acid, 120, was lactonized under Yamaguchiconditions to furnish 122, and removal of the remaining silyl ethersusing trifluoroacetic acid gave 9,10-didehydroepothilone D (124).

[0105] Scheme 9 illustrates the synthesis of a bislactone analog, 134,of the epothilones. Bislactone 134 was assayed for tubulinpolymerization activity as well as antiproliferative action relative topaclitaxel and epothilones B and D. The biological data are recorded inTable 2.

[0106] As depicted in Scheme 9, allylic alcohol 104 was coupled to acid81 via a Mitsunobu reaction to afford compound 126. The resultant estercompound was selectively deprotected to yield hydroxy acid 130, whichunderwent lactonization under Yamaguchi conditions to afford thebislactone 132. Cleavage of the remaining silyl ethers gave targetcompound 134.

[0107] Compounds 126 and 128 are used to synthesize the correspondinglactam and thiolactone epothilone analogs, respectively. The lactam andthiolactone can be prepared in analogous fashion to the bislactone 132.Amine 126 is readily available by the present method from compound 57.For example, compound 57 has been converted to the corresponding allylichalide 106 (Scheme 6). Such an allylic halide can be converted to amine126 via the corresponding allylic azide (not shown) as is known to thoseof ordinary skill in the art. Similarly, compound 128 can be preparedfrom compound 106 via displacement of the allylic halide usingthioacetic acid, and followed by removal of the acetyl moiety to providecompound 128.

[0108] Trans 9,10-dehydroepothilone 146 can be prepared according toScheme 10 from aldehyde 76 and compound 140 via a Julia olefination.According to this route, treatment of compound 140 (available fromcompound 106) with a base, such as butyl lithium, forms thecorresponding sulfonyl carbanion. The carbanion then reacts withaldehyde 76 to provide a hydroxy sulfone product (not shown). Theβ-hydroxy sulfone is eliminated under reductive conditions to give 9E,12Z, 16E-heptadecanoate derivative 142. Selective removal of thetriethylsilyl and trimethylsilyl ethyl ester protecting groups from 142,followed by macrolactonization under Yamaguchi conditions, providescompound 144 Removal of the remaining silyl protecting groups affordstrans 9,10-dehydroepothilone 146.

IV. EXAMPLES

[0109] The following examples are provided to illustrate certainparticular features of working embodiments of the disclosed method. Thescope of the present invention should not be limited to those featuresdescribed.

Example 1

[0110] This example describes the synthesis of compound 44 of Scheme 1.To a stirred solution of the alcohol precursor to 44 (1.03 g, 5.20 mmol)in CH₂Cl₂ (20 mL) was sequentially added DHP (580 mg, 630 μL, 6.91mmol), followed by PPTS (110 mg, 0.438 mmol). After 1.5 hours, thereaction was quenched with solid NaHCO₃ (5 g), filtered, concentrated invacuo and purified by chromatography over silica gel, eluting with 30%Et₂O/petroleum ether, to give 44 (1.42 g, 5.00 mmol, 96%) as a colorlessoil: IR (neat) 2940, 1445 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 6.04 (s, 1H),4.62 (t, J=3.0 Hz, 1H), 4.26 (d, J=12.1 Hz, 1H), 4.16 (d, J=12.1 Hz,1H), 3.85-3.95 (m, 1H), 3.5-3.6 (m, 1H), 1.95 (d, J=1.5 Hz, 3H), 1.5-1.9(m, 6H); ¹³C NMR (75 MHz, CDCl₃) δ 144.6, 98.4, 75.8, 72.1, 62.5, 30.7,25.6, 22.2, 19.6; HRMS (CI) calculated for C₉H₁₆O₂ (M⁺H⁺) 283.0195,found 283.0198.

Example 2

[0111] This example describes the synthesis of compound 46. To a stirredsolution of t-BuLi (48 mL, 62.4 mmol, 1.3 M in pentane) in Et₂O (63 mL)at −78° C. was added a solution of 44 (10.27 g, 36.4 mmol) in Et₂O (75mL) via syringe pump over 20 minutes. After 20 minutes, the slurry wasrapidly transferred to a precooled solution of CuCN (1.58 mg, 17.7 mmol)in THF (122 mL) at −78° C. After 1 hour at −78° C. and 5 minutes at −40°C., the solution was recooled to −78° C., and a precooled solution of 42(3.40 g, 14.7 mmol) in THF (86 mL) was added via cannula. An additionalamount of THF (25 mL) was added to rinse the flask. After 30 minutes,the solution was warmed to 0° C., and after a further 10 minutes thereaction was quenched with saturated aqueous NH₄Cl (300 mL) andextracted with Et₂O (3×150 mL). The dried (MgSO₄) extract wasconcentrated in vacuo and purified by chromatography over silica gel,eluting with 15-50% Et₂O/petroleum ether, to give 46 (5.05 mg, 13.1mmol, 89%) as a colorless oil: [α]D²³+46.1 (c 2.58, CHCl₃); IR (neat)1782, 1699 cm⁻¹; ¹H NMR (300 MHz, CDCl₃)δ 7.1-7.4 (m, 5H), 5.40 (t,J=7.1 Hz, 1H), 4.6-4.7 (m, 2H), 4.05-4.2 (m, 4H), 3.8-3.95 (m, 1H),3.45-3.6 (m, 1H), 3.28 (dd, J=3.2, 13.3 Hz, 1H), 2.9-3.05 (m, 2H), 2.76(dd, J=9.6, 13.3 Hz, 1H), 2.46 (q, J=7.3 Hz, 2H), 1.5-1.9 (m, 6H), 1.78(s, 3H); ¹³C NMR (75 MHz, CDCl₃) δ 172.8, 153.6, 135.5, 133.8, 129.6,129.1, 127.5, 127.4, 97.8, 97.7, 66.4, 65.5, 65.4, 62.3, 55.3, 38.1,36.0, 30.8, 25.7, 22.7, 21.9, 19.7; HRMS (FAB) calculated for C₂₂H₂₈NO₅(M+H⁺) 386.1968, found 386.1965.

Example 3

[0112] This example describes the synthesis of compound 48. To a stirredsolution of NaHMDS (7.6 mL, 7.6 mmol, 1 M in THF) in THF (35 mL) at −78°C. was added a solution of the alcohol precursor to 46 (2.482 g, 6.41mmol) in THF (50 mL) via syringe pump over 30 minutes. An additionalamount of THF (5 mL) was added to rinse the syringe. After 20 minutes, aprecooled solution of oxaziridine (2.55 g, 9.77 mmol) in THF (8 mL) wasquickly added via cannula. After 6 minutes, the reaction was quenchedwith a solution of CSA (3.54 g, 15.2 mmol) in THF (10 mL). After 2minutes, saturated aqueous NH₄Cl (75 mL) was added. The mixture wasallowed to warm to room temperature and was concentrated in vacuo toremove THF. The aqueous layer was extracted with Et₂O (4×100 mL). Thedried (MgSO₄) extract was concentrated in vacuo and purified bychromatography over silica gel, eluting with 50-70% Et₂O/petroleumether, followed by chromatography over silica gel, eluting with 2-4%acetone/CH₂Cl₂, followed by trituration in 10% Et₂O/petroleum ether togive 48 (1.84 g, 4.5 mmol, 71%) as a white foam contaminated with asmall amount of the phenyl sulfonamide: [α]D²³+37.2 (c 4.00, CHCl₃); IR(neat) 3476, 1781, 1699 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 7.1-7.4 (m, 5H),5.40 (m, 1H), 5.05-5.15 (m, 1H), 4.55-4.7 (m, 2H), 4.05-4.3 (m, 4H),4.02 (dd, J=3.7, 11.7 Hz, 1H), 3.8-3.95 (m, 1H), 3.79 (d, J=8.6 Hz, 1Hof a diastereomer), 3.66 (d, J=8.6 Hz, 1H of a diastereomer), 3.45-3.6(m, 1H), 3.31 (dt, J=3.0, 13.5 Hz, 1H), 2.75-2.9 (m, 1H), 2.45-2.6 (m,2H), 1.5-1.9 (m, 9H); ¹³C NMR (75 MHz, CDCl₃) δ 174.6, 174.3, 153.4,153.3, 136.2, 135.5, 135.11, 135.06, 129.6, 129.2, 127.6, 123.8, 123.1,98.1, 96.4, 70.5, 70.4, 67.1, 67.0, 65.7, 65.0, 62.4, 61.8, 55.7, 37.7,32.6, 30.7, 30.5, 25.6, 22.2, 22.1, 19.7, 19.2; HRMS (Cl) calculated forC₂₂H₂₈NO₆(M+H⁺) 402.1917, found 402.1919.

Example 4

[0113] This example describes the synthesis of compound 50. To a stirredsolution of 48 (1.74 g, 4.32 mmol) in CH₂Cl₂ (22 mL) at −78° C. wasadded sequentially 2,6-lutidine (1.06 g, 1.15 mL, 9.87 mmol) followed byTBSOTf (2.07 g, 1.8 mL, 7.83 mmol). After 30 minutes, the reaction wasquenched with saturated aqueous NH₄Cl (100 mL) and extracted with Et₂O(4×100 mL). The dried (MgSO₄) extract was concentrated in vacuo andpurified by chromatography over silica gel, eluting with 30-50%Et₂O/petroleum ether, to give 50 (2.06 g, 3.90 mmol, 90%) as a colorlessoil: [α]D²³+32.3 (c 2.96, CHCl₃); IR (neat) 1782, 1714 cm⁻¹; ¹H NMR (300MHz, CDCl₃) δ 7.15-7.4 (m, 5H), 5.35-5.5 (m, 2H), 4.55-4.7 (m, 2H),4.05-4.2 (m, 2H), 4.0-4.15 (m, 2H), 3.8-3.9 (m, 1H), 3.4-3.5 (m, 1H),3.36 (d, J=13.1 Hz, 1H), 2.7-2.8 (m, 1H), 2.71 (dt, J=1.6, 10.1 Hz, 1H),2.45-2.55 (m, 2H), 1.5-1.8 (m, 9H), 0.92 (s, 9H), 0.91 (s, 9H of adiastereomer), 0.11 (s, 3H of a diastereomer), 0.10 (s, 3H of adiastereomer), 0.08 (s, 3H of a diastereomer), 0.07 (s, 3H of adiastereomer); ¹³C NMR (75 MHz, CDCl₃) δ 173.9, 173.7, 153.3, 135.5,134.9, 129.6, 129.1, 127.5, 124.0, 97.6, 96.9, 71.1, 66.7, 65.5, 65.2,62.3, 61.9, 55.8, 37.9, 34.2, 33.7, 30.8, 30.7, 26.0, 25.7, 22.0, 21.9,19.7, 19.4, 18.5, −4.6, −4.9; HRMS (CI) calculated for C₂₈H₄₄NO₆Si (M)518.2938, found 518.2908.

Example 5

[0114] This example describes the synthesis of compound 52. To a stirredsolution of EtSH (713 mg, 850 FL, 11.5 mmol) in THF (45 mL) was added KH(106 mg, 0.93 mmol, 35% in mineral oil). After 30 minutes, the mixturewas cooled to 0° C. and a solution of 50 (2.064 g, 3.99 mmol) in THF (15mL) was added via cannula over 5 minutes. An additional amount of THF(10 mL) was added to rinse the flask. After 50 minutes at roomtemperature, the reaction was quenched with saturated aqueous NH₄Cl (50mL). Air was bubbled through the solution for 2 hours to remove excessEtSH. The solution was extracted with Et₂O (4×100 mL). The dried (MgSO₄)extract was concentrated in vacuo and the residue was crystallized bythe addition of 10% Et₂O/petroleum ether to yield the recoveredauxiliary (640 mg, 3.61 mmol, 93%) as a white solid. The decantedsolution was purified by chromatography over silica gel, eluting with10-30% Et₂O/petroleum ether, to give 52 (1.44 g, 3.50 mmol, 90%) as acolorless oil: [α]D²³-46.1 (c 3.50, CHCl₃); IR (neat) 1684 cm⁻¹; ¹H NMR(300 MHz, CDCl₃) 5.35-5.5 (m, 1H), 4.55 (bs, 1H), 3.9-4.2 (m, 3H),3.8-3.9 (m, 1H), 3.45-3.6 (m, 1H), 2.75-2.9 (m, 2H), 2.4-2.6 (m, 2H),1.4-1.9 (m, 6H), 1.21 (t, J=7.5 Hz, 3H), 0.93 (s, 9H), 0.09 (s, 3H),0.06 (s, 3H of a diastereomer), 0.05 (s, 3H of a diastereomer); ¹³C NMR(75 MHz, CDCl₃) δ 205.1, 205.0, 135.24, 135.16, 97.9, 97.4, 78.6, 65.7,65.5, 62.3, 62.2, 34.5, 30.8, 25.9, 25.7, 22.6, 22.1, 22.0, 19.7, 19.6,18.4, 14.8, −4.7, −4.8; HRMS (CI) calculated for C₂₀H₃₇NO₄SSi (M+H⁺)401.2182, found 401.2172.

Example 6

[0115] This example describes the synthesis of compound 54. To a stirredsolution of CuI (4.85 mg, 25.5 mmol) in Et₂O (120 mL) at 0° C. was addedMeLi (33.1 mL, 23.2 mmol, 1.4 M in Et₂O). After 15 minutes, the solutionwas cooled to-50° C. and a solution of 52 (1.78 g, 4.64 mmol) in Et₂O(90 mL) was added via cannula. An additional amount of Et₂O (10 mL) wasadded to rinse the flask. After 30 minutes, the reaction was quenchedwith saturated aqueous NH₄Cl (300 mL) and extracted with Et₂O (4×175mL). The dried (MgSO₄) extract was concentrated in vacuo and purified bychromatography over silica gel, eluting with 15% Et₂O/petroleum ether,to give 54 (1.36 g, 3.81 mmol, 82%) as a colorless oil: [α]D²³+14.0 (c5.00, CHCl₃); IR (neat) 1719 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 5.35-5.5(m, 5H), 4.5-4.55 (m, 1H), 3.9-4.1 (m, 3H), 3.75-3.9 (m, 1H), 3.4-3.5(m, 1H), 2.3-2.5 (m, 2H), 2.10 (s, 3H), 1.74(s, 3H), 1.4-1.9 (m, 6H),0.87 (s, 9H), 0.00 (s, 6H); ¹³C NMR (75 MHz, CDCl₃) δ 211.7, 135.2,135.1, 123.8, 123.5, 97.7, 97.3, 79.0, 65.5, 65.2, 62.2, 62.1, 33.2,30.7, 25.8, 25.6, 25.5, 22.0, 19.6, 19.5, 18.2, −4.8, −4.9; HRMS (CI)calculated for C₁₉H₃₇O₄Si (M+H⁺) 357.2461, found 357.2455.

Example 7

[0116] This example describes the synthesis of compound 56. To a stirredsolution of the phosphonate (1.45 g, 5.82 mmol) in THF (10 mL) at −78°C. was added n-BuLi (3.6 mL, 5.76 mmol, 1.6 M in hexanes). After 15minutes, a solution of 54 (590 mg, 1.66 mmol) in THF (7 mL) was addedvia cannula. An additional amount of THF (3 mL) was added to rinse theketone flask. After 30 minutes, the mixture was allowed to warm to roomtemperature over 1 hour. After an additional 30 minutes, the reactionwas quenched with saturated aqueous NH₄Cl (50 mL) and extracted withEt₂O (4×75 mL). The dried (MgSO₄) extract was concentrated in vacuo andpurified by chromatography over silica gel, eluting with 10-20%Et₂O/petroleum ether, to give sequentially the undesired olefin isomer(40 mg, 0.089 mmol, 5%) as a colorless oil followed by the desiredproduct 54 (690 mg, 1.52 mmol, 92%) as a colorless oil: Minordiastereomer: [α]D²³-59.2 (c 1.26, CHCl₃); IR (neat) 2959, 2852, 1022cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 6.79 (s, 1H), 6.18, (s, 1H), 5.35-5.5(m, 2H), 4.55-4.65 (m, 1H), 4.05-4.15 (m, 2H), 3.8-3.9 (m, 1H), 3.45-3.6(m, 1H), 2.68 (s, 3H), 2.4-2.5 (m, 1H), 2.2-2.35 (m, 1H), 1.87 (d, J=0.9Hz, 3H), 1.76 (s, 3H), 1.4-1.9 (m, 6H), 0.84 (s, 9H), 0.07 (s, 3H),−0.10 (s, 3H); ¹³C NMR (75 MHz, CDCl₃) δ 164.4, 152.9, 143.5, 133.4,126.7, 126.5, 118.8, 115.2, 97.9, 97.6, 70.8, 70.5, 65.9, 62.4, 62.2,34.5, 30.9, 26.0, 25.7, 22.1, 19.8, 19.7, 19.4, 18.5, 18.4, −4.7, −4.9.Major diastereomer: [α]D²³+19.2 (c 3.45, CHCl₃); IR (neat) 2959, 1531,1474 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 6.91 (s, 1H), 6.45, (s, 1H),5.35-5.5 (m, 1H), 4.5-4.6 (m, 1H), 3.9-4.2 (m, 3H), 3.8-3.9 (m, 1H),3.45-3.6 (m, 1H), 2.70 (s, 3H), 2.2-2.4 (m, 2H), 1.99 (d, J=1.0 Hz, 3H),1.76 (s, 3H) 1.4-1.9 (m, 6H), 0.88 (s, 9H), 0.04 (s, 3H), −0.01 (s, 3H);¹³C NMR (75 MHz, CDCl₃) δ 164.5, 153.4, 142.5, 142.4, 133.6, 126.2,126.1, 119.2, 118.9, 115.3, 97.8, 97.5, 79.0, 78.9, 65.8, 65.6, 62.3,62.2, 35.4, 35.3, 30.1, 26.9, 26.0, 25.7, 22.0, 19.7, 19.4, 18.4, 14.1,−4.5, −4.8; HRMS (CI) calculated for C₂₄H₄₂NO₃SSi (M+H⁺) 452.2655, found452.2645.

Example 8

[0117] This example describes the synthesis of the alcohol precursor tocompound 58. To a stirred solution of freshly prepared MgBr₂ (27.6 mmolof Mg, 23.8 mmol of BrCH₂CH₂Br, 50 mL of Et₂O) was added 56 (663 mg,1.26 mmol) in Et₂O (5 mL) at room temperature followed by saturatedaqueous NH₄Cl (approximately 50 μL). After 3.5 hours, the solution wascooled to 0° C. and carefully quenched with saturated aqueous NH₄Cl (50mL). The solution was extracted with Et₂O (4×70 mL), and the dried(MgSO₄) extract was concentrated in vacuo and purified by chromatographyover silica gel, eluting with 30-50% Et₂O/petroleum ether, to give thedesired alcohol (459 mg, 1.26 mmol, 99%) as a colorless oil: [α]D²³-16.8(c 3.40, CHCl₃); IR (neat) 3374 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 6.92 (s,1H), 6.44, (s, 1H), 5.31 (t, J=7.7 Hz, 1H), 4.14 (d, J=12.2 Hz, 1H),4.1-4.2 (m, 1H), 4.00 (d, J=12.2 Hz, 1H), 2.71 (s, 3H), 2.4-2.5 (m, 1H),2.2-2.3 (m, 2H), 2.00 (s, 3H), 1.80 (s, 3H), 0.89 (s, 9H), 0.06 (s, 3H),0.04 (s, 3H); ¹³C NMR (75 MHz, CDCl₃) δ 164.8, 153.0, 142.4, 137.7,124.4, 119.0, 115.4, 78.4, 62.0, 35.5, 26.0, 22.2, 19.3, 18.5, 14.3,−4.5, −4.7; HRMS (CI) calculated for C₁₉H₃₄NO₂SSi 368.2080. Found368.2061.

Example 9

[0118] This example describes the synthesis of compound 58. To a stirredsolution of the alcohol precursor (620 mg, 1.69 mmol) in CH₂Cl₂ (5.5 mL)at 0° C. was added Et₃N (360 FL, 2.58 mmol) followed by Ms₂O (390 uL,2.24 mmol). After 10 minutes, Me₂CO (5.5 mL) was added followed by LiBr(890 mg, 10.3 mmol). After 1.8 hours at room temperature, the mixturewas concentrated in vacuo to remove the acetone, diluted with saturatedaqueous NH₄Cl (100 mL), and extracted with Et₂O (4×200 mL). The dried(MgSO₄) extract was concentrated in vacuo and purified by chromatographyover silica gel, eluting with 10-20% Et₂O/petroleum ether, to give 58(607 mg, 1.44 μmol, 84%) as a colorless oil: [α]D²³+65.1 (c 2.95,CHCl₃); IR (neat) 2949, 2930, 2852, 1479, 844 cm⁻¹; ¹H NMR (300 MHz,CDCl₃) δ 6.93 (s, 1H), 6.48, (s, 1H), 5.42 (1 dt, J=1.3, 7.6 Hz, H),4.16 (dd, J=5.4, 7.3 Hz, 1H), 4.06 (d, J=9.5 Hz, 1H), 3.90 (d, J=9.5 Hz,1H), 2.71 (s, 3H), 2.3-2.5 (m, 2H), 2.01 (d, J=1.1 Hz, 3H), 1.83 (d,J=1.0 Hz, 3H), 0.88 (s, 9H), 0.04 (s, 3H), 0.01 (s, 3H); ¹³C NMR (75MHz, CDCl₃) δ 164.6, 153.2, 142.1, 133.3, 128.2, 119.2, 115.4, 78.1,35.7, 32.6, 26.0, 22.2, 19.4, 18.4, 13.1, −4.5, −4.8; HRMS (CI)calculated for C₁₉H₃₃NO₂SSiBr (M+H⁺) 430.1235, found 430.1244.

Example 10

[0119] This example describes the synthesis of compound 60. To a stirredsolution of Ph₃PMeBr (1.53 g, 4.28 mmol) in THF (16.2 mL) at −78° C. wasadded n-BuLi (2.7 mL, 4.32 mmol, 1.6 M in hexanes) over a period of 3minutes. After 35 minutes, a pre-cooled solution of 58 (607 mg, 1.41mmol) in THF (7 mL) was added dropwise to the ylide over a period of 5minutes. An additional portion of THF (6 mL) was added to rinse theflask. After 15 minutes, the mixture was allowed to warm to −20° C.After an additional 20 minutes, the reaction was quenched with MeOH, andwas concentrated in vacuo. The residue was purified by chromatographyover silica gel, eluting with 0-6% MeOH/CH₂Cl₂, followed by dilutionwith CH₂Cl₂ and an H₂O wash to remove excess Ph₃MeBr, to give 60 (890mg, 1.26 mmol, 89%) as an off-white foam: [α]D²³+6.4 (c 1.06, CHCl₃); IR(neat) 2959, 2930, 2853, 1440; ¹H NMR (300 MHz, CDCl₃) δ 7.6-7.9 (1 m,SH), 6.89 (s, 1H), 6.33, (s, 1H), 5.20 (m, 1H), 3.95 (m, 1H), 3.5-3.8(m, 2H), 2.65 (s, 3H), 2.1-2.3 (m, 2H), 1.88 (s, 3H), 1.83 (s, 3H), 0.78(s, 9H), −0.07 (s, 3H), −0.09 (s, 3H); ¹³C NMR (75 MHz, CDCl₃) δ 164.7,153.0, 142.1, 135.6, 133.9, 130.9, 130.7, 124.7, 118.8, 117.5, 115.6,78.2, 35.9, 26.0, 24.7, 23.7, 22.6, 21.9, 19.4, 18.3, 14.4, −4.6, −4.8;HRMS (CI) calculated for C₃₈H₄₉NOPSSi (M+H) 626.3042, found 626.3028.

Example 11

[0120] This example describes the synthesis of compound 66. To a stirredsolution of i-Pr₂NH (390 μL, 2.78 mmol) in THF (0.7 mL) was added n-BuLi(1.73 mL, 2.77 mmol, 1.6 M in hexanes) dropwise at −78° C. After 5minutes, the solution was warmed to 0° C. for 45 minutes and recooled to−78° C. To the stirring solution of LDA was added a precooled solutionof 62 (718 mg, 2.53 mmol) in THF (0.6 mL) dropwise via cannula over 5minutes. An additional amount of THF (0.4 mL) was used to rinse theflask. After an additional 50 minutes at −78° C., a precooled solutionof 64 (484 mg, 2.33 mmol) in THF (0.6 mL) was added dropwise viacannula. An additional amount of THF (0.4 mL) was used to rinse theflask. After 30 minutes, the reaction was quenched with saturatedaqueous NH₄Cl (20 mL) and extracted with Et₂O (4×25 mL). The dried(MgSO₄) extract was concentrated in vacuo and purified by chromatographyover silica gel, eluting with 6-10% Et₂O/petroleum ether, to give 66(694mg, 1.41 mmol, 61%) as a colorless oil: [α]D²³−25.1 (c 3.05, CHCl₃); IR(neat) 3483, 1695 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 7.25 (d, J=8.7 Hz,2H), 6.86 (d, J=8.7 Hz, 2H), 5.65-5.85 (m, 1H), 4.9-5.1 (m, 2H), 4.44(s, 2H), 3.93 (dd, J=4.5, 6.4 Hz, 1H), 3.80 (s, 3H), 3.55-3.65 (m, 3H),3.46 (dd, J=6.1, 8.9 Hz, 1H), 3.15-3.25 (m, 1H), 2.05-2.2 (m, 2H),1.8-1.9 (m, 1H), 1.18 (s, 3H), 1.11 (s, 3H), 1.05 (d, J=6.8 Hz, 3H),0.94 (d, J=7.9 Hz, 3H), 0.89 (s, 9H), 0.07 (s, 3H), 0.06 (s, 3H); ¹³CNMR (75 MHz, CDCl₃) δ 221.7, 159.3, 136.5, 130.9, 129.4, 116.9, 113.9,73.2, 73.1, 72.9, 55.4, 54.4, 41.9, 39.8, 36.4, 29.9, 26.3, 23.9, 19.3,18.4, 14.3, 10.2, −3.3, −3.8; HRMS (CI) calculated for C₂₈H₄₉O₅Si (M+H⁺)493.3349, found 493.3350.

Example 12

[0121] This example describes the synthesis of compound 68. To a stirredsolution of 66 (61 mg, 0.124 mmol) in CH₂Cl₂ (0.7 mL) at 0° C. wassequentially added Et₃N (29 mg, 40 mL, 0.287 mmol) followed by TBSOTf(43.7 mg, 38 μL, 0.165 mmol) at 0° C. After 45 minutes, the reaction wasquenched with saturated aqueous NH₄Cl (20 mL) and extracted with Et₂O(4×25 mL). The dried (MgSO₄) extract was concentrated in vacuo andpurified by chromatography over silica gel, eluting with 3-10%Et₂O/petroleum ether, to give 68(66.5 mg, 0.111 mmol, 89%) as acolorless oil: [α]D²³-16.0 (c 2.92, CHCl₃); IR (neat) 1695 cm⁻¹; ¹H NMR(300 MHz, CDCl₃) δ 7.23 (d, J=8.6 Hz, 2 h), 6.86 (d, J=8.6 Hz, 2 h),5.7-5.9 (m, 1H), 4.99 (d, J=6.4 Hz, 1H), 4.95 (s, 1H), 4.40 (s, 2H),3.9-4.0 (m, 1H), 3.85 (d, J=7.3 Hz, 1H), 3.80 (s, 3), 3.58 (dd, J=5.7,9.2 Hz, 1H), 3.27 (qn, J=7.4 Hz, 1H), 3.19 (t, J=7.4 Hz, 1H) 2.0-2.2 (m,2H), 1.8-1.9 (m, 1H), 1.13 (s, 3H), 1.04 (s, 3H), 1.02 (3H, d, J=7.0Hz), 0.96 (3H, d, J=6.9 Hz), 0.891 (s, 9H), 0.887 (s, 9H), 0.06 (s, 6H),0.05 (s, 3H), 0.03 (s, 3H); ¹³C NMR (75 MHz, CDCl₃) δ 219.2, 159.3,137.1, 131.0, 129.5, 116.5, 113.9, 76.5, 73.1, 71.8, 55.5, 54.2, 46.2,39.8, 38.9, 26.5, 26.3, 25.3, 18.7, 18.4, 18.0, 17.0, 16.6, −3.0, −3.3,−3.5, −3.8; HRMS (CI) calculated for C₃₄H₆₃O₅Si₂ (M+H⁺) 607.4214, found607.4212.

Example 13

[0122] This example describes the synthesis of compound 70. To a stirredsolution of 68(722 mg, 1.19 mmol) in THF (9 mL) and H₂O (8.5 mL) wassequentially added OSO₄ (400 μL, 4% in H₂0) followed by NaIO₄ (1.065 g,4.98 mmol). After 18 hours, the reaction was quenched with saturatedaqueous Na₂S₂O₃ (50 mL). After 30 minutes, saturated aqueous NaCl (100mL) was added and the mixture was extracted with Et₂O (4×100 mL). Thedried (MgSO₄) extract was concentrated in vacuo to give the aldehyde asa colorless oil: [α]_(D) ²³−13.0 (c 4.20, CHCl₃); IR (neat) 1725, 1689cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 9.74 (It, J=1.2 Hz, 11H), 7.22 (d, J=8.5Hz, 2 h), 6.85 (d, J=8.5 Hz, 2H), 4.46 (t, J=5.3 Hz, 1H), 4.39 (s, 2H),3.82 (d, J=7.9 Hz, 1H), 3.80 (s, 3H), 3.58 (dd, J=6.0, 9.1 Hz, 1H), 3.27(qn, J=7.4 Hz, 1H), 3.19 (dd, J=6.9, 8.9 Hz, 1H) 2.3-2.5 (m, 2H),1.6-1.8 (m, 1H), 1.14 (s, 3H), 1.06 (s, 3H), 1.00 (d, J=7.0 Hz, 3H),0.94 (d, J=7.0 Hz, 3H), 0.88 (s, 9H), 0.87 (s, 9H), 0.08 (s, 3H), 0.05(s, 6H), 0.03 (s, 3H); ¹³C NMR (75 MHz, CDCl₃) δ 219.0, 201.5 159.3,130.9, 129.5, 113.9, 76.8, 73.1, 71.7, 71.6, 55.4, 53.7, 49.7, 46.2,38.8, 26.4, 26.1, 24.4, 18.7, 18.3, 17.0, 15.7, −3.4, −3.5, −3.9, −4.3;HRMS (CI) calculated for C₃₃H₆₁O₆Si₂ (M+H⁺) 609.4007, found 607.4005.

[0123] To a stirred solution of the crude aldehyde (1.19 mmol) preparedabove in t-BuOH (16 mL) and H₂O (15 mL) was sequentially added2-methyl-2-butene (3 mL) followed by NaH₂PO₄ (1.06 g, 11.6 mmol) andNaClO₂ (490 mg, 5.4 mmol). After 1 hour, the reaction was quenched withsaturated aqueous NaCl (75 mL) and extracted with Et₂O (4×100 mL). Thedried (MgSO₄) extract was concentrated in vacuo to give crude 70 as acolorless oil: [α]_(D) ²³−26.8 (c 4.20, CHCl₃); IR (neat) 2400-3400,1722 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 7.23 (d, J=8.6 Hz, 2H), 6.85 (d,J=8.6 Hz, 2H), 4.40 (s, 2H), 4.3-4.4 (m, 1H), 3.82 (d, J=7.9 Hz, 1H),3.80 (s, 3H), 3.58 (dd, J=5.8, 9.1 Hz, 1H), 3.32 (qn, J=7.2 Hz, 1H),3.18 (dd, J=7.2, 8.9 Hz, 1H) 2.46 (dd, J=2.9, 16.4 Hz, 1H), 2.28 (dd,J=6.8, 16.4 Hz, 1H), 1.7-1.85 (m, 1H), 1.15 (s, 3H), 1.07 (s, 3H), 1.02(d, J=6.9 Hz, 3H), 0.95 (d, J=7.0 Hz, 3H), 0.88 (s, 9H), 0.87 (s, 9H),0.08 (s, 3H), 0.05 (s, 6H), 0.04 (s, 3H); ¹³C NMR (75 MHz, CDCl₃) δ218.7, 178.0, 159.3, 130.9, 129.5, 113.9, 73.8, 73.1, 71.7, 55.5, 53.7,46.3, 40.4, 38.9, 26.4, 26.4, 26.2, 24.0, 18.7, 18.4, 17.0, 15.8, −3.3,−3.5, −4.1, −4.4; HRMS (CI) calculated for C₃₃H₆₁O₇Si₂ 625.3966. Found625.3957.

Example 14

[0124] This example describes the synthesis of compound 72. To a stirredsolution of crude 70 (1.19 mmol) in PhH (20 mL) and MeOH (2.5 mL) wasadded TMSCHN₂ (700 μL, 1.4 mmol, 2 M in hexanes). After 45 minutes, themixture was concentrated in vacuo and purified by chromatography oversilica gel, eluting with 5-10% Et₂O/petroleum ether, to give 72 (502 mg,0.797 mmol, 66% over three steps) as a colorless oil: [α]_(D)−27.1 (c1.03, CHCl₃); IR (neat) 1741, 1690 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 7.23(d, J=8.5 Hz, 2H), 6.86 (d, J=8.5 Hz, 2H), 4.39 (s, 2H), 4.3-4.4 (m,1H), 3.83 (d, J=7.8 Hz, 1H), 3.80 (s, 3H), 3.66 (s, 3H), 3.58 (dd,J=5.7, 9.1 Hz, 1H), 3.31 (qn, J=7.2 Hz, 1H), 3.18 (dd, J=7.3, 9.1 Hz,1H), 2.46 (dd, J=3.1, 16.1 Hz, 1H), 2.26 (dd, J=7.0, 16.1 Hz, 1H),1.7-1.85 (m, 1H), 1.14 (s, 3H), 1.06 (s, 3H), 1.01 (d, J=6.9 Hz, 3H),0.95 (d, J=6.9 Hz, 3H), 0.88 (s, 9H), 0.87 (s, 9H), 0.08 (s, 3H), 0.05(s, 6H), 0.02 (s, 3H); ³C NMR (75 MHz, CDCl₃) δ 218.5, 172.7, 159.3,131.0, 129.5, 113.9, 74.1, 73.1, 71.8, 55.5, 53.6, 51.8, 46.3, 40.4,38.9, 26.5, 26.2, 24.0, 18.8, 18.7, 18.4, 17.0, 15.7, −3.3, −3.5, −4.3,−4.4; HRMS (CI) calculated for C₃₃H₆₃O₇Si₂ (M+H⁺) 639.4112, found639.4112.

Example 15

[0125] This example describes the synthesis of compound 74. To a stirredsolution of 72 (290 mg, 0.455 mmol) in EtOH (7 mL) was added palladiumon carbon (101 mg, 10% Pd) and the mixture was placed under anatmosphere of H₂. After 0.75 hour, the H₂ atmosphere was replaced by Arand the reaction was filtered through Celite (EtOH rinse). The liquidwas concentrated in vacuo and the residue was purified by chromatographyover silica gel, eluting with 10-30% Et₂O/petroleum ether, to give 74(216 mg, 0.418 mmol, 92%) as a colorless oil: [α]_(D) ²³−13.2 (c 1.07,CHCl₃); IR (neat) 3538, 1743, 1694 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 4.40(dd, J=2.9, 6.9 Hz, 1H), 3.93 (dd, J=2.0, 7.8 Hz, 1H), 3.67 (s, 3H),3.6-3.7 (m, 1H), 3.5-3.6 (m, 1H), 3.31 (qn, J=7.5 Hz, 1H), 2.43 (dd,J=2.7, 16.3 Hz, 1H), 2.26 (dd, J=6.9, 16.3 Hz, 1H), 1.55-1.65 (m, 1H),1.22 (s, 3H), 1.13 (s, 3H), 1.09 (d, J=7.0 Hz, 3H), 0.95 (d, J=7.1 Hz,3H), 0.92 (s, 9H), 0.87 (s, 9H), 0.12 (s, 3H), 0.10 (s, 3H), 0.09 (s,3H), 0.01 (s, 3H); ¹³C NMR (75 MHz, CDCl₃) δ 218.4, 172.8, 78.2, 73.6,64.9, 53.9, 51.9, 47.0, 40.3, 39.8, 29.9, 26.4, 26.2, 24.1, 19.1, 18.6,18.4, 16.1, −3.4, −3.6, −4.3, −4.4; HRMS (CI) calculated for C₂₆H₅₁Si₂O₆(M⁺H⁺) 517.3381, found 517.3361.

Example 16

[0126] This example describes the synthesis of compound 76. To a stirredsolution of 74(700 mg, 1.36 mmol) and powdered molecular sieves (1.5 g)in CH₂Cl₂ (35 mL) was sequentially added NMO (420 mg, 3.56 mmol)followed by TPAP (137.5 mg, 106 mmol). After 1 hour, the mixture wasdiluted with 30% Et₂O/petroleum ether (100 mL) and filtered throughsilica gel (30% Et₂O/petroleum ether rinse). The filtrate wasconcentrated in vacuo to give 76 (698 mg, 1.36 mmol, 99%) as a colorlessoil: [α]_(D) ²³−32.1 (c 1.76, CHCl₃); IR (neat) 1746, 1690 cm⁻¹; ¹H NMR(300 MHz, CDCl₃) δ9.73 (d, J=2.1 Hz, 1H), 4.41 (dd, J=3.2, 6.9 Hz, 1H),4.08 (dd, J=2.1, 8.3 Hz, 1H), 3.67 (s, 3H), 3.25 (qn, J=7.0 Hz, 1H),2.41 (1Hdd, J=3.3, 16.1 Hz, 1H), 2.2-2.35 (m, 2H), 1.24 (s, 3H), 1.12(d, J=7.1 Hz, 3H), 1.10 (d, J=6.9 Hz, 3H), 1.09 (s, 3H), 0.89 (s, 9H),0.87 (s, 9H), 0.11 (s, 3H), 0.090 (s, 3H), 0.085 (s, 3H), 0.01 (s, 3H);¹³C NMR (75 MHz, CDCl₃) δ 218.0, 204.4, 172.6, 76.5, 73.9, 53.8, 51.9,51.0, 46.8, 40.4, 29.9, 26.4, 24.0, 19.2, 18.6, 18.4, 15.9, 12.7, −3.4,−3.6, −4.3, −4.4; HRMS (CI) calculated for C₂₆H₅₁Si₂O₆ (M+H⁺) 515.3225,found 515.3218.

Example 17

[0127] This example describes the synthesis of compound 78. To LHMDS[HMDS (280 μL, 1.31 mmol) in THF (650 μL) at −78° C. was added n-BuLi(820 μL, 1.31 mmol, 1.6 M in hexanes). After 5 minutes, the solution waswarmed to 0° C. and added dropwise to a stirred solution of the salt 58(930 mg, 1.32 mmol) in THF (17 mL) at −78° C. via cannula. After 15minutes, the solution was warmed to −30° C. After an additional 15minutes, the solution was re-cooled to −78° C. and added dropwise to apre-cooled solution of the 76 (520 mg, 1.03 mmol) in THF (0.6 mL) viacannula. The mixture was then allowed to warm slowly to room temperatureover a period of 1 hour. After 10 minutes at room temperature, thereaction was quenched with saturated aqueous NH₄Cl (25 mL) and wasconcentrated in vacuo to remove THF. The solution was extracted withEt₂O (4×50 mL), and the dried (MgSO₄) extract was concentrated in vacuoand purified by chromatography over silica gel, eluting with 2-10%Et₂O/petroleum ether, to give 78 (728 mg, 0.84 mmol, 82%) as a colorlessoil: [α]_(D) ²³+3.6 (c 1.00, CHCl₃); IR (neat) 1743, 1699 cm⁻¹; ¹H NMR(300 MHz, CDCl₃) δ 6.91 (s, 1H), 6.45 (s, 1H), 5.58 (t, J=9.2 Hz, 1H),5.2-5.35 (m, 1H), 5.16 (t, J=6.6 Hz, 1H), 4.39 (1H, dd, J=3.1, 6.9 Hz),4.09 (1H, t, J=6.6 Hz), 3.8-3.9 (m, 1H), 3.6-3.7 (m, 1H); 3.66 (s, 3H),3.03 (qn, J=6.7 Hz, 1H), 2.70 (s, 3H), 2.65-2.75 (m, 2H), 2.3-2.5 (m,2H), 2.15-2.35 (m, 3H), 1.99 (s, 3H), 1.64 (s, 3H), 1.19 (s, 3H), 1.06(s, 3H), 1.03 (d, J=7.1 Hz, 3H), 1.00 (d, J=7.0 Hz, 3H), 0.92 (s, 9H),0.88 (s, 9H), 0.86 (s, 9H), 0.08 (s, 3H), 0.07 (s, 6H), 0.04 (s, 3H),0.00 (s, 3H), −0.01 (s, 3H); ¹³C NMR (75 MHz, CDCl₃) δ 218.0, 172.6,164.5, 153.4, 142.5, 135.5, 131.7, 128.7, 122.2, 119.0, 115.2, 79.1,76.1, 74.2, 53.5, 51.8, 46.4, 40.4, 37.9, 35.6, 30.9, 26.4, 26.2, 26.0,24.0, 23.9, 19.4, 19.3, 18.7, 18.4, 14.9, 14.1, −3.3, −3.7, −4.3, −4.4,−4.7; HRMS (CI) calculated for C₄₆H₈₆O₆Si₃SN (M+H⁺) 864.5484, found864.5510.

Example 18

[0128] This example describes the synthesis of compound 80. To a stirredsolution of 78 (51 mg, 59 μmol) in i-PrOH (1 mL) was added NaOH (11.5FL, 62 μmol, 5.4 M in H₂O), and the mixture was heated at 45° C. in asealed tube. After 16 hours, the solution was concentrated, diluted withaqueous HCl (20 mL, 0.5 M) and extracted with Et₂O (4×50 mL). The dried(MgSO₄) extract was concentrated in vacuo and purified by chromatographyover silica gel, eluting with 5-20% EtOAc/hexanes, to give 80 (33 mg, 34μmol, 66%) as a colorless oil: IR (neat) 3500-2500, 1713 cm⁻¹; ¹H NMR(300 MHz, CDCl₃) δ 6.93 (s, 1H), 6.67 (s, 1H), 5.52 (t, J=9.6 Hz, 1H),5.3-5.4 (m, 1H), 5.23 (t, J=7.4 Hz, 1H), 4.41 (dd, J=3.3, 6.6 Hz, 1H),3.75-3.85 (m, 1H), 2.9-3.1 (m, 2H), 2.71 (s, 3H), 2.5-2.8 (m, 2H),2.1-2.6 (m, 4H), 1.9-2.1 (m, 1H), 1.93 (s, 3H), 1.71 (s, 3H), 1.16 (s,3H), 1.13 (s, 3H), 1.04 (d, J=7.0 Hz, 3H), 9.94 (obscured d, 3H), 0.92(s, 9H), 0.88 (18H, s), 0.12 (s, 6H), 0.09 (s, 3H), 0.06 (s, 3H), 0.03(s, 3H), −0.01 (s, 3H); HRMS (CI) calculated for C₄₅H₈₄O₆Si₃SN (M+H⁺)850.5327, found 850.5281.

Example 19

[0129] This example describes the synthesis of compound 82. To a stirredsolution of 80(154 mg, 181 μmol) in THF (3.9 mL) at 0° C. was added TBAF(1.1 mL, 1.1 mmol, 1 M in THF). The solution was allowed to warm slowlyto room temperature overnight. After 16 hours, the mixture was dilutedwith EtOAc, washed with saturated aqueous NH₄Cl (50 mL), and extractedwith EtOAc (4×100 mL). The dried (MgSO₄) extract was concentrated invacuo and purified by chromatography over silica gel, eluting with 2-5%MeOH/CH₂Cl₂, to give 82 (118.5 mg, 160 μmol, 89%) as a white foam:[α]_(D) ²³−2.6 (c 3.50, CHCl₃); IR (neat) 3500-2500, 1709 cm⁻¹;

[0130]¹H NMR (300 MHz, CDCl₃) δ 6.95 (s, 1H), 6.70 (s, 1H), 5.56 (t,J=10.0 Hz, 1H), 5.3-5.45 (m, 11H), 5.24 (t, J=7.3 Hz, 1H), 4.35-4.45 (m,11H), 4.16 (t, J=6.2 Hz, 1H), 3.75-3.85 (m, 1H), 3.03 (m, 2H), 2.75-2.85(m, 1H), 2.72 (s, 3H), 2.65-2.75 (m, 1H), 2.2-2.7 (m, 5H), 1.99 (s, 3H),1.74 (s, 3H), 1.15 (s, 3H), 1.14 (s, 3H), 1.04 (d, J=7.1 Hz, 3H), 0.98(d, J=6.9 Hz, 3H), 0.92 (s, 9H), 0.87 (s, 9H), 0.12 (s, 3H), 0.10 (s,3H), 0.07 (s, 3H), 0.06 (s, 3H); ¹³C NMR (75 MHz, CDCl₃) δ 218.1, 176.0,165.1, 152.4, 141.9, 137.5, 131.6, 127.8, 120.8, 118.8, 115.1, 77.2,76.0, 73.5, 53.6, 46.3, 40.1, 38.0, 34.1, 30.8, 26.2, 26.0, 23.7, 23.5,19.0, 18.9, 18.7, 18.5, 18.1, 15.0, 14.6, −3.6, −4.1, −4.2, −4.6; HRMS(CI) calculated for C₃₉H₇₀O₆Si₂SN (M+H⁺) 736.4462, found 736.4451.

Example 20

[0131] This example describes the synthesis of the protected alcoholprecursor to compound 84. To a stirred solution of 82 (57.2 mg, 78.0μmol) in THF (1.3 mL) at 0° C. was added Et₃N (19 FL, 136 mmol) followedby 2,4,6-trichlorobenzoyl chloride (14 μL, 89.5 mmol). After 45 minutes,the mixture was diluted with THF (1 mL) and PhMe (1.7 mL) and was addedvia syringe pump to a stirring solution of DMAP (16.3 mg, 133 μmol) inPhMe (18 mL) at 75° C. over a period of 3.5 hours. After an additional 1hour, the solution was cooled, diluted with EtOAc, washed with saturatedaqueous NH₄Cl (50 mL), and extracted with EtOAc (4×100 mL). The dried(MgSO₄) extract was concentrated in vacuo and purified by chromatographyover silica gel, eluting with 2-10% EtOAc/hexanes, to give the protectedalcohol precursor to compound 84 (35.5 mg, 49.5 mmol, 63%) as acolorless oil contaminated with a small amount of an oligomer: IR (neat)1738, 1709 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 6.95 (s, 1H), 6.50 (s, 1H),5.65 (t, J=10.0 Hz, 1H), 5.3-5.45 (m, 2H), 5.11 (t, J=6.3 Hz, 1H), 4.45(dd, J=2.8, 8.0 Hz, 1H), 3.7-3.8 (m, 1H), 3.19 (dd, J=9.5, 15.7 Hz, 1H),3.0-3.1 (m, 1H), 2.71 (s, 3H), 2.2-2.7 (m, 6H), 2.09 (s, 3H), 1.74 (s,3H), 1.13 (s, 3H), 1.11 (s, 3H), 1.07 (d, J=7.1 Hz, 3H), 0.99 (d, J=7.0Hz, 3H), 0.93 (s, 9H), 0.87 (s, 9H), 0.14 (s, 3H), 0.11 (s, 3H), 0.07(s, 3H), 0.06 (s, 3H); ³C NMR (75 MHz, CDCl₃) δ 216.0, 169.9, 164.9,152.9, 137.8, 136.5, 130.8, 126.9, 121.1, 118.9, 116.6, 106.3, 78.1,76.4, 73.1, 54.0, 47.4, 41.2, 39.0, 31.0, 26.4, 26.3, 26.1, 24.5, 21.3,20.5, 19.7, 19.5, 18.9, 18.3, 15.2, 14.7, −3.4, −3.5, −4.6; HRMS (CI)calculated for C₃₉H₆₈O₅Si₂SN (M+H⁺) 718.4357, found 718.4354.

Example 21

[0132] This example describes the synthesis of compound 84. To a stirredsolution of the protected alcohol precursor to compound 82 (16.5 mg, 23mmol) in CH₂Cl₂ (110 μL) at 0° C. was added TFA (100 μL). After 4.5hours, the mixture was concentrated in vacuo and purified bychromatography over silica gel, eluting with 20-50% EtOAc/hexanes, togive 84 (9.3 mg, 19 μmol, 83%) as a colorless oil: [α]_(D) ²³−133.0 (c1.30, CHCl₃); IR (neat) 3438, 1738, 1694 cm⁻¹; ¹H NMR (400 MHz, CDCl₃) δ6.97 (s, 1H), 6.52 (s, 1H), 5.5-5.7 (m, 2H), 5.35-5.45 (m, 1H), 5.15 (t,J=7.1 Hz, 1H), 4.22 (dd, J=2.5, 9.4 Hz, 1H), 3.7-3.8 (m, 1H), 3.1-3.2(m, 1H), 3.04 (dd, J=7.7, 15.3 Hz, 1H), 2.85-2.95 (m, 1H), 2.70 (s, 3H),2.4-2.7 (m, 6H), 2.06 (s, 3H), 1.72 (s, 3H), 1.27 (s, 3H), 1.1-1.2(obscured d, 3H×2), 1.12 (s, 3H); ¹³C NMR (100.5 MHz, CDCl₃) δ 220.4,170.7, 152.2, 138.1, 137.0, 132.3, 128.1, 119.0, 118.9, 115.7, 77.4,74.1, 73.0, 52.7, 44.2, 39.1, 36.9, 31.4, 30.2, 29.7, 23.9, 21.8, 20.4,19.0, 17.5, 16.0, 13.3; HRMS (CI) calculated for C₂₇H₄₀O₅SN (M+H⁺)490.2627, found 490.2627.

Example 22

[0133] This example describes the synthesis of 86. To a stirred solutionof 84 (6.6 mg, 13.5 μmol) in CH₂Cl₂ (2 mL) at reflux was addedportionwise a large excess of KO₂CN═NCO₂K followed by AcOH (2equivalents) until the reaction was complete by TLC (25 hours). The KOAcprecipitate was periodically removed during the course of the reaction.The solution was filtered through SiO₂ (Et₂O rinse), concentrated invacuo, and purified by chromatography over silica gel, eluting withEtOAc/hexanes/CH₂Cl₂ (1:4:5-1:1:2), to give 86 (3.4 mg, 6.9 mmol, 52%)as a colorless oil: [α]_(D) ²³−86.7 (c 0.15, CHCl₃); ¹H NMR (400 MHz,CDCl₃) δ 6.95 (s, 1H), 6.58 (s, 1H), 5.22 (d, J=8.8 Hz, 1H), 5.1-5.2 (m,1H), 4.30 (d, J=11.2 Hz, 1H), 3.7-3.8 (m, 1H), 3.4-3.55 (m, 1H), 3.15(q, J=4.8 Hz, 1H), 3.0-3.1 (m, 1H), 2.69 (s, 3H), 2.5-2.7 (m, 1H),2.05-2.5 (m, 4H), 2.06 (s, 3H), 1.8-1.9 (m, 1H), 1.7-1.8 (m, 1H), 1.34(s, 3H), 1.2-1.3 (m, 4H), 1.19 (d, J=7.0 Hz, 3H), 1.07 (s, 3H), 1.01 (d,J=6.9, 3H); ¹³C NMR (100.5 MHz, CDCl₃) δ 220.8, 170.6, 165.2, 152.3,139.4, 138.7, 121.1, 119.5, 115.9, 79.2, 74.4, 72.6, 53.7, 42.0, 39.9,32.8, 32.0, 31.9, 25.6, 23.1, 19.3, 18.3, 16.1, 16.0, 13.6.

Example 23

[0134] This example describes the synthesis of compound 4. To a stirredsolution of 86 (1.5 mg, 3.05 mmol) in CH₂Cl₂ (400 mL) at −50° C. wasadded a solution of dimethyl dioxirane until all of the startingmaterial had been consumed as judged by TLC. The solution wasconcentrated in vacuo and purified by chromatography over silica gel,eluting with 50-60% EtOAc/pentane, to give epothilone B (4) (1.2 mg, 2.4mmol, 78%) as a colorless oil: [α]_(D) ²³−36.7 (c 0.12, CHCl₃); ¹H NMR(400 MHz, CDCl₃) δ 6.97 (s, 1H), 6.59 (s, 1H), 5.42 (dd, J=2.8, 7.9 Hz,1H), 4.1-4.3 (m, 2H), 3.77 (bs, 1H), 3.2-3.35 (m, 1H), 2.81 (dd, J=4.5,7.6 Hz, 1H), 2.69 (s, 3H), 2.66 (bs, 1H), 2.4-2.55 (m, 1H), 2.36 (dd,J=2.3, 13.6 Hz, 1H), 2.1-2.2 (m, 1H), 2.09 (s, 3H), 1.85-2.0 (m, 1H),1.6-1.7 (m, 1H), 1.35-1.55 (m, 4H), 1.37 (s, 3H), 1.28 (s, 3H), 1.17 (d,J=6.8 Hz, 3H), 1.08 (s, 3H), 1.00 (d, J=7.1 Hz); ¹³C NMR (100.5 MHz,CDCl₃) 6220.6, 170.5, 165.1, 151.8, 137.5, 119.7, 116.1, 74.1, 72.9,61.6, 61.3, 53.1, 42.9, 39.2, 36.4, 32.3, 32.1, 30.8, 29.7, 22.7, 22.3,21.4, 19.6, 19.1, 17.0, 15.8, 13.6; HRMS (CI) calculated for C₂₇H₄₂NO₅S(M+H⁺) 492.2784, found 492.2775.

Example 24

[0135] This example describes the synthesis of alkyne 88 as illustratedin Scheme 4. To a stirred solution of potassium tert-butoxide (0.27 mL,1.0 M THF solution) in THF (0.5 mL) at −78° C. was added a solution of(diazomethyl)phosphonate (40.2 mg, 1.25 mmol) in THF (0.5 mL). After 5minutes a solution of 76 (110 mg, 0.21 mmol) in THF (0.5 mL) was addeddropwise, and the mixture was stirred at −78° C. for 12 hours. Themixture was then warmed to room temperature and was quenched withsaturated aqueous NH₄Cl. The aqueous layer was extracted with 3×5 mLportions of Et₂O, and the combined organic extracts were dried (MgSO₄),concentrated in vacuo, and purified by chromatography (SiO₂, 5%Et₂O/hexane) to give 88 (85 mg, 80%) as colorless crystals: [α]_(D)²⁴−24.1 (c 1.12, CHCl₃); mp 52-54° C.; IR (film) 3310 2951, 2927, 2883,2854, 1743, 1691, 1472, 1254, 1089, 990, 837, 775 cm⁻¹; ¹H NMR (CDCl₃,300 MHz) δ 4.45 (1H, dd, J=3.1, 7.5 Hz), 3.76 (1H dd, J=2.1, 6.4 Hz),3.65 (1H, s), 3.33 (1H, qn, J=7.5) 2.40-2.26 (3H, m), 2.06 (1H, s), 1.24(3H, s), 1.18 (3H, d, J=6.9 Hz), 1.17 (3H, 3H), 1.07 (3H, d, J=7.0 Hz),0.92 (9H, s), 0.86 (9H, s), 0.08 (3H, s), 0.07 (3H, s), 0.00 (3H, s);¹³C NMR (CDCl₃, 75 MHz) δ 218.6, 172.3, 85.6, 75.7, 73.3, 70.8, 53.9,46.5, 32.1, 26.1, 23.7, 18.7, 18.5, 18.2, 15.8, −3.3, −3.9, −4.5, −4.7;HRMS (CI) calculated for C₂₇H₅₂Si₂Os (M+H⁺) 512.3353, found 512.3342.

Example 25

[0136] This example describes the synthesis of enyne 90 as illustratedin Scheme 4. To a stirred solution of 88 (70.0 mg, 0.135 mmol) in Et₂O(1.0 mL) and DMF (0.4 mL) at room temperature was added Et₃N (18.8 μL,0.135 mmol) and CuI (25.7 mg, 0.135 mmol). After the mixture turnedclear (approximately 5 minutes), a solution of 56 (29.1 mg, 0.068 mmol)in Et₂O (1.0 mL) was added, and the mixture was stirred for 18 hours.The reaction mixture was quenched with saturated aqueous Na₂S₂O₃ (5 mL)and was extracted with Et₂O (3×2 mL). The combined organic extracts weredried (MgSO₄), concentrated in vacua, and purified by flashchromatography over silica gel (50-60% CH₂Cl₂/hexanes) to give 90 (35.6mg, 60%) as a colorless oil: [α]_(D) ²³−16.7 (c 1.01); IR (film) 2927,2857, 2371, 2341, 1743, 1683, 1648, 1482, 1251, 991, 837 cm⁻¹; ¹H NMR(CDCl₃, 300 MHz) δ 6.91(1H, s), 6.46 (1H, s), 5.36 (1H, t, J=4.7 Hz),4.45 (1H, dd, J=3.1, 6.9), 4.11 (1H, t, J=6.6), 3.76-3.72 (1H, m),3.74-3.67 (1H, m), 3.67 (3H, s), 3.36-3.31 (1H, qn, J=6.8), 2.71 (3H,s), 2.41-2.25 (7H, m), 2.01 (3H, s), 1.80 (3H, s), 1.24 (3H, s), 1.16(3H, s), 1.12 (3H, d, J=7.0), 1.05 (3H, d, J=6.8), 0.92 (9H, s), 0.88(9H, s), 0.87 (9H, s), 0.09 (3H, s), 0.06 (6H, s), 0.04 (3H, s), 0.01(3H, s), −0.00 (3H, s); ¹³C NMR (CDCl₃, 75 MHz): δ 218.0, 172.4, 164.3,153.2, 142.5, 132.2, 122.2, 118.6, 118.9, 83.1, 80.2, 78.6, 75.9, 73.5,53.7, 51.6, 46.3, 40.4, 35.7, 32.6, 29.7, 29.2, 26.1, 26.0, 25.8, 23.8,21.7, 19.2, 18.9, 18.4, 18.2, 16.2, 15.7, 13.9, −3.3, −3.9, −4.4, −4.6,−4.7, −4.9; HRMS (CI) calculated for C₄₆H₃₄O₆Si₃SN (M+H⁺) 862.5327,found 862.5325.

Example 26

[0137] This example describes the synthesis of methyl ester 80 fromcompound 90 as illustrated in Scheme 4. A suspension of 90 (10 mg, 0.011mmol) and Lindlar's catalyst (1.35 mg, 5% Pd) was stirred at roomtemperature under an atmosphere of H2 for 28 hours. The suspension wasfiltered through silica gel (Et₂O rinse), concentrated in vacuo, andpurified by flash chromatography over silica gel (40-60% CH₂Cl₂/hexane)to give 80 (6.8 mg, 68%) as a colorless oil: [α]_(D) ²⁴+3.6 (c 1.00,CHCl₃); IR (film) 1743, 1699 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 6.91 (1H,s), 6.45 (1H, s), 5.58 (1H, t, J=9.2 Hz), 5.2-5.35 (1H, m), 5.16 (1H, t,J=6.6 Hz), 4.39 (1H, dd, J=3.1, 6.9 Hz), 4.09 (1H, t, J=6.6 Hz), 3.8-3.9(1H, m), 3.6-3.7 (1H, m); 3.66 (3H, s), 3.03 (1H, qn, J=6.7 Hz), 2.70(3H, s), 2.65-2.75 (2H, m), 2.3-2.5 (2H, m), 2.15-2.35 (3H, m), 1.99(3H, s), 1.64 (3H, s), 1.19 (3H, s), 1.06 (3H, s), 1.03 (3H, d, J=7.1Hz), 1.00 (3H, d, J=7.0 Hz), 0.92 (9H, s), 0.88 (9H, s), 0.86 (9H, s),0.08 (3H, s), 0.07 (6H, s), 0.04 (3H, s), 0.00 (3H, s), −0.01 (3H, s); CNMR (75 MHz, CDCl₃) δ 218.0, 172.6, 164.5, 153.4, 142.5, 135.5, 131.7,128.7, 122.2, 119.0, 115.2, 79.1, 76.1, 74.2, 53.5, 51.8, 46.4, 40.4,37.9, 35.6, 30.9, 26.4, 26.2, 26.0, 24.0, 23.9, 19.4, 19.3, 18.7, 18.4,14.9, 14.1, −3.3, −3.7, −4.3, −4.4, −4.7; HRMS (CI) calculated forC₄₆H₈₆O₆Si₃SN (M+H⁺) 864.5484, found 864.5510.

Example 27

[0138] This example describes the saponification of methyl ester 90 toform carboxylic acid 80 as illustrated in Scheme 4. To a stirredsolution of the methyl ester (51 mg, 59 μmol) in i-PrOH (1 mL) was addedNaOH (11.5 μL, 62 μmol, 5.4 M in H₂O), and the mixture was heated at 45°C. in a scaled tube. After 16 hours, the solution was concentrated,diluted with aqueous HCl (20 mL, 0.5 M) and extracted with Et₂O (4×50mL). The dried (MgSO₄) extract was concentrated in vacuo and purified bychromatography over silica gel, eluting with 5-20% EtOAc/hexanes, togive acid 80 (33 mg, 34 mmol, 66%) as a colorless oil: IR (neat)3500-2500, 1713 cm¹; ¹H NMR (300 MHz, CDCl₃) δ 6.93 (s, 1H), 6.67 (s,1H), 5.52 (t, J=9.6 Hz, 1H), 5.3-5.4 (m, 1H), 5.23 (t, J=7.4 Hz, 1H),4.41 (dd, J=3.3, 6.6 Hz, 1H), 3.75-3.85 (m, 1H), 2.9-3.1 (m, 2H), 2.71(s, 3H), 2.5-2.8 (m, 2H), 2.1-2.6 (m, 4H), 1.9-2.1 (m, 1H), 1.93 (s,3H), 1.71 (s, 3H), 1.16 (s, 3H), 1.13 (s, 3H), 1.04 (d, J=7.0 Hz, 3H),9.94 (obscured d, 3H), 0.92 (s, 9H), 0.88 (18H, s), 0.12 (s, 6H), 0.09(s, 3H), 0.06 (s, 3H), 0.03 (s, 3H), −0.01 (s, 3H); HRMS (CI) calculatedfor C₄₅H840₆Si₃SN (M+H⁺) 850.5327, found 850.5281.

Example 28

[0139] This example describes the deprotection of carboxylic acid 80 toform triene 82 as illustrated in Scheme 4. To a stirred solution ofcarboxylic acid 80 (154 mg, 181 μmol) in THF (3.9 mL) at 0° C. was addedTBAF (1.1 mL, 1.1 mmol, 1 M in THF). The solution was allowed to warmslowly to room temperature overnight. After 16 hours, the mixture wasdiluted with EtOAc, washed with saturated aqueous NH₄Cl (50 mL), andextracted with EtOAc (4×100 mL). The dried (MgSO₄) extract wasconcentrated in vacuo and purified by chromatography over silica gel,eluting with 2-5% MeOH/CH₂Cl₂, to give 82 (118.5 mg, 160 μmol, 89%) as awhite foam: [α]_(D) ²³−2.6 (c 3.50, CHCl₃); IR (neat) 3500-2500, 1709cm¹; ¹H NMR (300 MHz, CDCl₃) δ 6.95 (s, 1H), 6.70 (s, 1H), 5.56 (t,J=10.0 Hz, 1H), 5.3-5.45 (m, 1H), 5.24 (t, J=7.3 Hz, 1H), 4.35-4.45 (m,1H), 4.16 (t, J=6.2 Hz, 1H), 3.75-3.85 (m, 1H), 3.03 (m, 2H), 2.75-2.85(m, 1H), 2.72 (s, 3H), 2.65-2.75 (m, 1H), 2.2-2.7 (m, 5H), 1.99 (s, 3H),1.74 (s, 3H), 1.15 (s, 3H), 1.14 (s, 3H), 1.04 (d, J=7.1 Hz, 3H), 0.98(d, J=6.9 Hz, 3H), 0.92 (s, 9H), 0.87 (s, 9H), 0.12 (s, 3H), 0.10 (s,3H), 0.07 (s, 3H), 0.06 (s, 3H); C NMR (75 MHz, CDCl₃) δ 218.1, 176.0,165.1, 152.4, 141.9, 137.5, 131.6, 127.8, 120.8, 118.8, 115.1, 77.2,76.0, 73.5, 53.6, 46.3, 40.1, 38.0, 34.1, 30.8, 26.2, 26.0, 23.7, 23.5,19.0, 18.9, 18.7, 18.5, 18.1, 15.0, 14.6, −3.6, −4.1, −4.2, −4.6; HRMS(CI) calculated C₃₉H₇₀O₆Si₂SN (M+H⁺) 736.4462, found 736.4451.

Example 29

[0140] This example describes the synthesis of compound 94. To a stirredsolution of 92 (195 mg, 0.32 mmol) in THF (1.5 mL) was added2-(trimethylsilyl)ethanol (69 PL, 0.48 mmol) and triphenylphosphine(56.8 mg, 0.80 mmol). The solution was cooled to 0° C. and diethylazodicarboxylate was added. After 1.5 hours, the reaction was quenchedwith saturated aqueous NH₄Cl, and the solution was extracted with Et₂O.The extract was concentrated in vacuo, and the residue was purified bychromatography on silica gel, eluting with 5-10% Et₂O/petroleum ether,to give 94 (175 mg, 75%) as a colorless oil: [α]_(D) ²³−27.0 (c 1.03,CHCl₃; IR (neat) 1741, 1690 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 7.23 (d,J=8.4 Hz, 2H), 6.85 (d, J=8.4 Hz, 2H), 4.39 (s, 2H), 4.3-4.4 (m, 1H),3.83 (d, J=7.8 Hz, 1H), 3.80 (s, 3H), 3.58 (dd, J=5.7, 9.1 Hz, 1H), 3.31(dq, J=7.2, 7.2 Hz, 1H), 3.18 (dd, J=7.3, 9.1 Hz, 1H), 2.46 (dd, J=3.1,16.1 Hz, 1H), 2.26 (dd, J=7.0, 16.1 Hz, 1H), 1.7-1.85 (m, 1H), 1.14 (s,3H), 1.06 (s, 3H), 1.01 (d, J=6.9 Hz, 3H), 0.95 (d, J=6.9 Hz, 3H), 0.88(s, 9H,), 0.87 (s, 9H), 0.08 (s, 3H), 0.05 (s, 6H), 0.02 (s, 3H); ¹³CNMR (CDCl₃) δ 218.5, 172.7, 159.3, 131.0, 129.5, 113.9, 74.1, 73.1,71.8, 55.5, 53.6, 51.8, 46.3, 40.4, 38.9, 29.9, 26.5, 26.2, 24.0, 18.8,18.7, 18.4, 17.0, 15.7, −3.3, −3.5, −4.3, −4.4; HRMS (CI) calculated forC₃₈H7307Si (M+H⁺) 725.4664, found 725.4666.

Example 30

[0141] This example describes the synthesis of compound 95. To a stirredsolution of 94 (150 mg, 0.20 mmol) in EtOH (4.0 mL) was addedpalladium-on-carbon (55 mg, 10% Pd), and the mixture was stirred underan atmosphere of H2. After 1 hours, the H2 atmosphere was replaced byAr, and the mixture was filtered through Celite (EtOH rinse). Thefiltrate was concentrated in vacuo, and the residue was purified bychromatography on silica gel, eluting with 10-30% Et₂O/petroleum ether,to give 95 (108 mg, 89%) as a colorless oil: [C]D²³−8.47 (c 1.18,CHCl₃); IR (neat) 3538, 1743, 1694 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 4.40(dd, J=2.9, 6.9 Hz, 1H), 4.17-4.11 (m, 2H) 3.93 (dd, J=2.0, 7.8 Hz, 1H),3.6-3.7 (m, 1H), 3.5-3.6 (m, 11H), 3.31 (dq, J=7.5, 7.5 Hz, 11H), 2.43(dd, J=2.7, 16.3 Hz, 1H), 2.26 (1H, dd, J=6.9, 16.3 Hz), 1.55-1.65 (1H,m), 1.22 (3H, s), 1.13 (3H, s), 1.09 (d, J=7.0 Hz, 3H), 0.95 (d, J=7.1Hz, 3H), 0.92 (s, 9H), 0.87 (s, 9H), 0.85 (m, 2H), 0.02 (s, 9H) 0.12 (s,3H), 0.10 (s, 3H), 0.09 (s, 3H), 0.01 (s, 3H); ¹³C NMR (CDCl₃) δ 218.4,172.8, 78.2, 73.6, 64.9, 60.3, 53.9, 51.9, 47.0, 40.3, 39.8, 29.9, 26.4,26.2, 24.1, 19.1, 18.6, 18.4, 17.2 16.1, −3.0, −3.4, −3.6, −4.3, −4.4.

Example 31

[0142] This example describes the synthesis of compound 96. To a stirredmixture of 95 (200 mg, 0.33 mmol) and powdered molecular sieves (300 mg)in CH₂Cl₂ (6.0 mL) was added sequentially N-methylmorpholine-N-oxide (97mg, 0.83 mmol) followed by tetra-n-propylammonium perruthenate (11.6 mg,33 μmol). After 1.5 hours, the mixture was filtered through silica (Et₂Orinse), and the filtrate was concentrated in vacuo to give the crudealdehyde as a colorless oil.

[0143] To a stirred solution of the crude aldehyde and K₂CO₃ (91 mg,0.66 mmol) in MeOH (5.0 mL) was added dimethyl1-diazo-2-oxopropylphosphonate (74 mg, 0.46 mmol). The solution wasstirred for 4 hours at room temperature, diluted with Et₂O (30 mL),washed with aqueous NaHCO₃ (5%), and extracted with Et₂O (3×30 mL). Thedried (MgSO₄) extract was concentrated in vacuo, and the residue waspurified by flash chromatography on silica gel, eluting with 2%Et₂O/hexanes, to give 96 (155 mg, 78%) as a colorless oil: [α]D²³-25.1(c 2.50, CHCl₃); IR (neat) 2946, 2928, 2848, 1734, 1690, 1468; ¹H NMR(300 MHz, CDCl₃) δ 4.45 (dd, J=3.1, 7.5 Hz, 1H), 4.11-4.16 (m, 2H), 3.76(dd, J=2.1, 6.4 Hz, 1H), 3.35 (dq, J=7.3, 7.3 Hz, 1H), 2.22-2.24 (m,3H), 2.06 (s, 1H),1.25 (s, 3H), 1.18 (d, J=7.5 Hz, 3H), 1.17 (s, 3H),1.07 (d, J=6.8 Hz, 3H), 0.95 (obscured m, 2H) 0.92 (s, 9H), 0.86 (s,9H), 0.10 (s, 3H), 0.07 (s, 3H), 0.07 (s, 3H), 0.03 (s, 9H), 0.02 (s,3H); ¹³C NMR (75 MHz, CDCl₃) δ 218.6, 172.1, 85.6, 75.7, 73.3, 70.8,62.7, 53.8, 46.5, 40.6, 32.2, 26.1, 26.0, 18.7, 18.5, 18.2, 17.2, 15.9,−1.6, −3.3, −3.9, −4.4, −4.7; HRMS (FAB) calculated for C₅₁H₆₃O₅Si₃(M+H⁺) 599.3983, found 599.3982.

Example 32

[0144] This example describes the synthesis of compound 98. To a stirredsolution of 96(60.0 mg, 0.10 mmol) and bis(triphenylphosphine)palladiumdichloride (1.4 mg, (0.002 mmol) in THF (0.5 mL) at room temperature wasadded slowly tri-n-butyltin hydride (32.3 μL, 0.12 mmol). After 10minutes, the solution was concentrated in vacuo, and the residue waspurified by chromatography on silica gel, eluting with 5% Et₂O/hexanes,to give 98 (79 mg, 89%) as a colorless oil: [α]_(D) ²³−9.6 (c 1.35,CHCl₃); IR (neat) 2955, 2928, 2856, 1736, 1472 cm⁻¹; ¹H NMR (300 MHz,CDCl₃) δ 6.12 (dd, J=7.5, 19.3 Hz, 1H), 5.89 (d, J=19.3 Hz, 11H), 4.43(dd, J=3.2, 6.8 Hz, 1H), 4.15 (m, 2H), 3.85 (dd, J=1.5, 7.9 Hz, 1H),3.07 (dq, J=7.1, 7.1 Hz, 1H), 2.40 (dd, J=3.2, 16.2 Hz, 1H), 2.23 (dd,J=6.8, 16.2 Hz, 1H), 1.45-1.53 (m, 6H), 1.23-1.37 (m, 12H), 1.19 (s,3H), 1.09 (s, 3H), 1.03 (d, J=7.0, 3H), 1.03 (d, J=6.9, 3H), 0.93 (s,9H), 0.87 (s, 9H), 0.85-0.93 (m, 12H), 0.10 (s, 3H), 0.09 (s, 3H), 0.08(s, 3H), 0.04 (s, 9H), 0.03 (s, 3H); ¹³C NMR (100 MHz, CDCl₃) δ 218.8,172.6, 150.7, 129.1, 74.0, 63.1, 53.9, 47.5, 47.1, 41.0, 29.6, 27.7,26.6, 26.4, 24.5, 19.2, 18.9, 17.7, 15.9, 14.1, 9.9, −1.1, −2.9, −3.4,−4.0, −4.3.

Example 33

[0145] This example describes the synthesis of compound 102. To astirred solution of 100 (1.00 g, 2.48 mmol) in CH₂Cl₂ (25 mL) at −78° C.was added 2,6-lutidine (61 mg, 0.66 mL, 5.72 mmol). After 4 minutes,triethylsilyl triflate (1.19 g, 1.0 mL, 4.5 mmol) was added to the coldsolution, and after 30 minutes the reaction was quenched with saturatedaqueous NH₄Cl (60 mL) and extracted with Et₂O (3×100 mL). The dried(MgSO₄) extract was concentrated in vacuo and the residue was purifiedby chromatography on silica gel, eluting with 30-50% Et₂O/hexane, togive 102 (1.00 g, 78%) as a colorless oil: [α]_(D) ²³+31.2 (c 1.63,CHCl₃); IR (neat) 1782, 1714 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 7.15-7.4(m, 5H), 5.35-5.5 (m, 2H), 4.55-4.7 (m, 2H), 4.05-4.2 (m, 2H), 4.0-4.15(m, 2H), 3.8-3.9 (m, 1H of a diastereomer), 3.4-3.5 (m, 1H of adiastereomer), 3.36 (d, J=13.1 Hz, 1H of a diastereomer), 2.7-2.8 (m, 1Hof a diastereomer), 2.45-2.55 (m, 2H), 2.46 (q, J=7.3 Hz, 1H), 1.5-1.8(m, 9H), 0.97 (t, J=7.8 Hz, 9H), 0.62 (q, J=7.6 Hz, 6H);¹³C NMR (75 MHz,CDCl₃) δ 173.9, 173.7, 153.3, 135.5, 134.9, 129.6, 129.1, 127.5, 124.0,97.6, 96.9, 71.1, 66.7, 65.5, 65.2, 62.3, 61.9, 55.8, 37.9, 34.2, 33.7,30.8, 30.7, 26.0, 25.7, 22.0, 21.9, 19.7, 19.4, 18.5, 6.7, 5.1; HRMS(CI) calculated for C₂₈H₄₄NO₆Si (M+H⁺) 518.2938, found 518.2908.

Example 34

[0146] This example describes the synthesis of compound 104. To astirred solution of ethanethiol (361 mg, 430 μL, 5.82 mmol) in THF (25mL) at room temperature was added KH (55 mg, 0.48 mmol, 35% in mineraloil). After 30 minutes, the mixture was cooled to 0° C. and a solutionof 102 (1.00 g, 1.94 mmol) in THF (10 mL) was added via cannula during 5minutes. An additional amount of THF (5 mL) was added, and after 1 hourat room temperature the reaction was quenched with saturated aqueousNH₄Cl (25 mL). Air was passed through the solution for 2 hours to removeexcess ethanethiol, and the mixture was extracted with Et₂O (3×100 mL).The dried (MgSO₄) extract was concentrated in vacuo and the residue wastaken up in 10% Et₂O/petroleum ether, from which 4benzyloxazolidin-2-one crystallized as a colorless solid. The decantedsolution was concentrated and the residue was purified by chromatographyon silica gel, eluting with 30% Et₂O/hexane, to give the thioester (730mg, 97%) as a colorless oil: [α]_(D) ²³−16.8 (c 2.73, CHCl₃); IR (neat)1684 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 5.35-5.5 (m, 1H), 4.55 (bs, 1H),3.9-4.2 (m, 3H), 3.8-3.9 (m, 1H), 3.45-3.6 (m, 1H), 3.36 (d, J=13.1 Hz,1H), 2.75-2.9 (m, 2H), 2.4-2.6 (m, 2H), 1.4-1.9 (m, 6H), 1.21 (t, J=7.5Hz, 3H), 0.97 (t, J=7.8 Hz, 9H), 0.62 (q, J=7.8 Hz, 6H); ¹³C NMR (75MHz, CDCl₃) δ 205.1, 205.0, 135.24, 135.16, 97.9, 97.4, 78.6, 65.7,65.5, 62.3, 62.2, 34.5, 30.8, 25.9, 25.7, 22.6, 22.1, 22.0, 19.7; 19.6,18.4, 14.8, 6.7, 5.1; HRMS (CI) calculated for C₂₀H₃₇NO₄SSi (M+H⁺)401.2182, found 401.2172

[0147] To a stirred solution of CuI (2.60 g, 13.67 mmol) in Et₂O (120mL) at 0° C. was added MeLi (17.8 mL, 24.9 mmol, 1.4M in Et₂O). Themixture was cooled to-50° C. and a solution of the thioester (960 mg,2.49 mmol) in Et₂O (50 mL) was added via cannula. An additional amountof Et₂O (5 mL) was added to rinse the flask. After 30 minutes, thereaction was quenched with saturated aqueous NH₄Cl (200 mL), and themixture was extracted with Et₂O (3×120 mL). The dried (MgSO₄) extractwas concentrated in vacuo and the residue was purified by chromatographyon silica gel, eluting with 15% Et₂O/hexane, to give the methyl ketone(548 mg, 62%) as a colorless oil: [α]D²³-11.0 (c 3.26, CHCl₃); IR (neat)1719 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 5.35-5.5 (m, 5H), 4.5-4.55 (m, 1H),3.9-4.1 (m, 3H), 3.75-3.9 (m, 11H), 3.4-3.5 (m, 1H), 2.3-2.5 (m, 2H),2.10 (s, 3H) 1.4-1.9 (m, 6H), 0.97 (t, J=7.8 Hz, 9H), 0.62 (q, J=7.8 Hz,6H); ¹³C NMR (75 MHz, CDCl₃) δ 211.7, 135.2, 135.1, 123.8, 123.5, 97.7,97.3, 79.0, 65.5, 65.2, 62.2, 62.1, 33.2, 30.7, 25.8, 25.6, 25.5, 22.0,19.6, 19.5, 18.2, 6.7, 5.1; HRMS (CI) calculated for C₁₉H3704Si (M+H⁺)357.2461, found 357.2455.

[0148] To a stirred solution of 53 (1.26 g, 5.08 mmol) in THF (9 mL) at−78° C. was added n-BuLi (4.7 mL, 5.00 mmol, 1.2 M in hexanes), andafter 20 minutes, a solution of the methyl ketone (520 mg, 1.45 mmol) inTHF (6 mL) was added via cannula. An additional amount of THF (2 mL) wasadded to rinse the flask. After 30 minutes, the solution was allowed towarm slowly to room temperature during 1 hour, then was cooled at −78°C. for an additional 30 minutes before the reaction was quenched withsaturated aqueous NH₄Cl (50 mL). The mixture was extracted with Et₂O(3×65 mL), and the dried (MgSO₄) extract was concentrated in vacuo. Theresidue was purified by chromatography on silica gel, eluting with 20%Et₂O/hexanes, to give the thiazole (627 mg, 96%) as a colorless oil:[α]D²³-33.9 (c 2.56, CHCl₃); IR (neat) 2950, 1512, 1455 cm⁻¹; ¹H NMR(300 MHz, CDCl₃) δ 6.91 (s, 1H), 6.45, (s, 1H), 5.35-5.5 (m, 1H),4.5-4.6 (m, 1H), 3.9-4.2 (m, 3H), 3.8-3.9 (m, 1H), 3.45-3.6 (m, 1H),2.70 (s, 3H), 2.2-2.4 (m, 2H), 1.99 (d, J=1.0 Hz, 3H), 1.4-1.9 (m, 6H),0.92 (t, J=7.9 Hz, 9H), 0.72 (q, J=7.9 Hz, 6H);¹³C NMR (75 MHz, CDCl₃,)δ 164.2, 153.1, 142.5, 142.2, 133.4, 125.6, 125.5, 118.7, 118.6, 114.9,97.4, 97.2, 78.4, 77.3, 65.4, 65.3, 62.0, 61.9, 35.0, 34.9, 30.6, 25.4,21.7, 19.4, 19.4, 19.1, 13.8, 6.7, 4.7; HRMS (CI) calculated forC₂₄H₄₂NO₃SSi (M+H⁺) 452.2655, found 452.2645.

[0149] To a stirred solution of freshly prepared MgBr₂(631 mg, 26.2 mmolof Mg, and 2.38 mL, 27.7 mmol, of 1,2-dibromoethane) in Et₂O (50 mL) atroom temperature was added the thiazole (556 mg, 1.20 mmol) in Et₂O (5mL) followed by saturated aqueous NH₄Cl (approximately 50 μL). After 3.5hours, the mixture was cooled to 0° C. and carefully quenched withsaturated aqueous NH₄Cl (50 mL). The mixture was extracted with Et₂O(3×100 mL), and the dried (MgSO₄) extract was concentrated in vacuo. Theresidue was purified by chromatography on silica gel, eluting with 30%Et₂O/hexanes, to give 104 (390 mg, 89%) as a colorless oil: [α]D²³-31.0(c 2.74); IR (neat) 3374 cm¹; ¹H NMR (300 MHz, CDCl₃) δ 6.92 (s, 11H),6.44, (s, 11H), 5.31 (t, J=7.7 Hz, 11H), 4.14 (d, J=12.2 Hz, 11H),4.1-4.2 (m, 11H), 4.00 (d, J=12.2 Hz, 1H), 2.71 (s, 3H), 2.4-2.5 (m,1H), 2.2-2.3 (m, 2H), 2.00 (s, 3H), 1.80 (s, 3H), 0.92 (t, J=7.9 Hz,9H), 0.72 (q, J=7.9 Hz, 6H);¹³C NMR (75 MHz, CDCl₃) δ 164.8, 153.0,142.4, 137.7, 124.4, 119.0, 115.4, 78.4, 62.0, 61.9, 35.5, 29.9, 26.0,22.2, 19.3, 18.5, 14.3, 6.7, 4.7; HRMS (CI) calculated for C₁₉H₃₄NO₂SSi(M+H⁺) 368.2080, found 368.2061.

Example 35

[0150] This example describes the synthesis of compound 106. To astirred solution of 104 (35 mg, 95 μmol) in CH₂Cl₂ (0.6 mL) at 0° C. wasadded Et₃N (23 μL, 161 μmol) followed by methanesulfonic anhydride (21mg, 119 μmol). After 10 minutes, acetone (0.6 mL) was added followed byLiCl (40 mg, 950 μmol). After 4 hours at room temperature, the solutionwas concentrated in vacuo to remove acetone, diluted with saturatedaqueous NH₄Cl, and extracted with Et₂O. The dried (MgSO₄) extract wasconcentrated in vacuo and the residue was purified by chromatography onsilica gel, eluting with 10-20% Et₂O/petroleum ether, to give 106 (36mg, 97%) as a colorless oil: [α]D²³+28.1 (c 1.11, CHCl₃); IR (neat)2954, 2875, 1453, 1072 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 6.94 (s, 1H),6.49 (s, 1H), 5.41 (dt, J=1.3, 7.5 Hz, 1H), 4.15 (m, 1H), 4.14 (d,J=10.8, 1H), 4.00 (d, J=10.8, 1H), 2.71 (s, 3H), 2.35 (m, 2H), 2.01 (d,J=1.2, 3H), 1.75 (d, J=1.2, 3H), 0.93 (t, J=7.69, 9H), 0.58 (q, J=7.39,6H); ¹³C NMR (75 MHz, CDCl₁₃) δ 164.5, 153.5, 142.3, 133.4, 127.8,119.4, 115.6, 78.4, 44.2, 35.8, 22.1, 19.6, 14.4, 7.2, 5.2; HRMS (FAB)calculated for C₁₉H₃₃ClNOSSi (M+H⁺) 386.1741, found 386.1737.

Example 36

[0151] This example describes the synthesis of compound 108. A solutionof 106 (44 mg, 114 μmol),tris(dibenzylideneactone)dipalladium-chloroform (7.1 mg, 6.8 μmol) andtriphenylarsine (8.4 mg, 27 μmol) in THF (0.4 mL) was stirred at roomtemperature for 10 minutes solution of 98 (107 mg, 120 μmol) in THF (1.0mL) was added, and the flask was briefly opened to the atmosphere,resealed, and heated to 65° C. After 18 hours, mixture was concentratedin vacuo and the residue was purified by chromatography on silica gel,eluting with 5% Et₂O/hexanes, to give 108 (82 mg, 76%) as a colorlessoil: [α]_(D) ²³−6.2 (c 1.23, CHCl₃); IR (neat) 2955, 2856, 1753, 1694,1471 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 6.91(s, 1H), 6.47 (s, 1H), 5.52(dd, J=7.9, 15.6 Hz, 1H), 5.32 (dt, J=6.7, 8.5 Hz, 1H), 5.17 (t, J=7.3,1H), 4.40 (dd, J=3.1, 6.7 Hz, 1H), 4.15-4.18 (m, 2H), 3.82 (dd, J=1.8,7.2, 1H), 3.02 (dq, J=7.1, 7.1 Hz, 1H), 2.72 (s, 3H), 2.66 (d, J=6.6 Hz,2H), 2.20-2.44 (m, 3H), 2.00 (s, 3H), 1.26 (s, 3H), 1.07 (s, 3H), 1.01(d, J=7.0 Hz, 3H), 1.00 (d, J=6.0 Hz, 3H), 0.93 (t, J=7.8 Hz, 9H), 0.91(s, 9H), 0.87 (s, 9H), 0.58 (q, J=7.8 Hz, 6H), 0.10 (s, 3H), 0.06 (s,3H), 0.03 (s, 3H), 0.03 (s, 9H), 0.02 (s, 3H); ¹³C NMR (75 MHz, CDCl₃) δ218.5, 172.6, 164.7, 153.6, 143.0, 136.0, 133.1, 129.7, 121.9, 119.0,115.3, 79.0, 76.8, 63.1, 53.8, 46.6, 43.8, 42.8, 40.9, 26.6, 26.4, 19.6,18.9, 18.6, 17.7, 16.7, 14.4, 7.3, 5.5, −1.1, −3.1, −3.4, −4.0, −4.2;HRMS (FAB) calculated for C₅₀H₉₆NO₆SSi₄ (M+H⁺) 950.6036, found 950.6065.

Example 37

[0152] This example describes the synthesis of compound 110. To astirred solution of 108 (20 mg, 21 μmol) and powdered molecular sieves(100 mg) in THF (8.0 mL) at 0° C. was added tetra-n-butylammoniumfluoride (16.5 mg, 63 μmol). After 6 hours, the mixture was filteredthrough glass wool, and aqueous citric acid (pH 5, 8 mL) was added tothe filtrate, which was extracted with Et₂O. The dried (MgSO₄) extractwas concentrated in vacuo and the residue was purified by flashchromatography on silica gel, eluting with 4% MeOH/CH₂Cl₂, to give 110(12.8 mg, 83%) as a colorless oil: [α]_(D) ²³−22.4 (c 2.15, CHCl₃); IR(neat) 3252, 2956, 2929, 2856, 1712 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 6.96(s, 1H), 6.58, (s, 1H), 5.54 (dd, J=7.5, 15.2 Hz, 1H), 5.38 (dt, J=6.7,15.2 Hz, 1H), 5.20 (t, J=7.8 Hz, 1H), 4.40 (dd, J=3.2, 6.4 Hz, 1H),4.16-4.24 (m, 1H), 3.83-3.86 (m, 1H), 3.02-3.09 (m, 1H), 2.72 (s, 3H),2.69-2.72 (m, 2H), 2.28-2.55 (m, 5H), 1.98-2.08 (m, 2H), 2.03 (s, 3H),1.63 (s, 3H), 1.17 (s, 3H), 1.12 (s, 3H), 1.04 (d, J=6.9 Hz, 3H), 0.97(d, J=6.9 Hz, 3H), 0.92 (s, 9H), 0.89 (s, 9H), 0.11 (s, 3H), 0.07 (s,3H), 0.07 (s, 3H), 0.06 (s, 3H)); ¹³C NMR (75 MHz, CDCl₃) δ 218.8,175.9, 165.4, 153.0, 142.1, 138.2, 133.3, 129.5, 120.6, 119.4, 115.7,76.9, 76.7, 73.7, 54.0, 46.8, 43.6, 42.8, 40.4, 34.6, 30.1, 26.6, 26.4,24.2, 20.1, 19.3, 18.9, 18.6, 16.9, 14.7, −3.1, −3.5, −3.7, −4.2; HRMS(FAB) calculated for C₃₉H₇₀NO₆SSi₂ (M+H⁺) 736.4462, found 736.4466.

Example 38

[0153] This example describes the synthesis of compound 112. To astirred solution of 110 (22.0 mg, 30.0 μmol) in THF (0.5 mL) at 0° C.was added Et₃N (7.6 μL, 54 μmol) followed by 2,4,6-trichlorobenzoylchloride (5.6 μL, 36 μmol). After 45 minutes, the mixture was dilutedwith THF (0.4 mL) and toluene (0.7 mL), and was added via syringe pumpto a stirred solution of DMAP (6.5 mg, 53 μmol) in toluene (7.2 mL) at75° C. during 3.5 h. After an additional 1 hour, the solution wasallowed to cool to room temperature, diluted with EtOAc, washed withsaturated aqueous NH₄Cl (20 mL), and extracted with EtOAc (4×40 mL). Thedried (MgSO₄) extract was concentrated in vacuo and the residue waspurified by chromatography on silica gel, eluting with 5% EtOAc/hexanes,to give 112 (19.4 mg, 71%) as a colorless oil: [α]D²³-2.12 (c 1.13,CHCl₃); IR (neat) 2929, 2856, 1735, 1700 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ6.94 (s, 3H), 6.54 (s, 3H), 5.44-5.46 (m, 2H), 5.28 (m, 1H), 5.22 (dd,J=3.3, 9.7, 1H), 4.63 (dd, J=3.2, 8.7, 1H), 3.90 (m, 1H), 3.16 (dq,J=6.8, 6.8 Hz, 1H), 2.71 (s, 3H), 2.20-2.71 (m, 6H), 2.14 (s, 3H), 1.68(s, 3H), 1.10 (d, J=6.8 Hz, 3H), 1.10 (s, 3H), 1.07 (s, 3H), 1.04 (d,J=7.0, 1H), 0.93 (s, 9H), 0.85 (s, 9H), 0.11 (s, 3H), 0.11 (s, 3H), 0.10(s, 3H), 0.88 (s, 3H); ¹³C NMR (100 MHz, CDCl₃) δ 215.9, 170.7, 165.1,153.1, 138.7, 137.8, 133.9, 128.3, 120.3, 119.8, 116.8, 80.8, 77.7,73.3, 55.1, 44.1, 43.1, 42.3, 42.0, 32.8, 26.6, 26.4, 21.2, 19.7, 19.1,18.9, 18.2, 18.0, 17.2, 15.2, −2.5, −3.4, −3.8, −3.8; HRMS (FAB)calculated for C₃₉H₆₈NO₅SSi₂ (M+H⁺) 718.4357, found 718.4345.

Example 39

[0154] This example describes the synthesis of compound 114 To a stirredsolution of 112 (14.5 mg, 20 μmol) in CH₂Cl₂ (125 μL) at 0° C. was addedtrifluoroacetic acid (112 μL). After 8 hours, the mixture wasconcentrated in vacuo, and the residue was purified by chromatography onsilica gel, eluting with 20-50% EtOAc/hexanes, to give 114 (9.3 mg, 19μmol, 95%) as a colorless waxy solid: [α]_(D) ²³-35.4 (c 0.50, CHCl₃);IR (neat) 2971, 2927, 1729, 1691 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 6.98(s, 1H), 6.55 (s, 1H), 5.53-5.48 (m, 2H), 5.38 (dd, J=2.8, 9.4 Hz, 11H),5.23 (m, 11H), 4.23 (dd, J=4.3, 8.2 Hz, 11H), 3.71 (m, 11H), 3.27 (dq,J=5.8, 6.7 Hz, 11H), 2.27-2.77 (m, 6H), 2.72 (s, 3H), 2.11 (s, 3H), 1.69(s, 3H), 1.26 (s, 3H), 1.17 (d, J=6.8 Hz, 3H), 1.10 (d, J=7.0 Hz, 3H),1.05 (s, 3H); ¹³C NMR (75 MHz, CDCl₃) δ 219.7, 171.0, 165.2, 152.7,138.4, 137.8, 132.8, 129.6, 120.4, 120.2, 116.6, 79.2, 77.0, 76.4, 74.6,72.3, 53.3, 44.7, 42.9, 40.3, 39.5, 32.6, 21.6, 20.0, 19.6, 17.8, 17.1,15.9, 15.2; HRMS (FAB) calculated for C₂₇H₄₀NO₃S (M+H⁺) 490.2627, found490.2634.

Example 40

[0155] This example describes the synthesis of compound 118. To astirred solution of alkyne 96 (38.0 mg, 0.063 mmol) in Et₂O (1.0 mL) andDMF (0.2 mL) at room temperature was added Et₃N (8.8 ILL, 0.063 mmol)and CuI (12.0 mg, 0.063 mmol). After the mixture became clear(approximately 5 minutes), a solution of chloride 59 (12.2 mg, 0.315mmol) in Et₂O (0.5 mL) was added. The solution was stirred for 18 hours,quenched with saturated aqueous Na₂S₂O₃ (5 mL), and extracted with Et₂O(3×2 mL). The combined extracts were dried (MgSO₄) and concentrated invacuo, and the residue was purified by chromatography on silica gel,eluting with 50-60% CH₂Cl₂/hexanes to give dienyne 118 (17.4 mg, 58%) asa colorless oil: [α]_(D) ²³−12.1 (c 1.74); IR (neat) 1737, 1692 cm⁻¹; ¹HNMR (CDCl₃, 300 MHz) δ 6.91(s, 1H), 6.47 (s, 1H), 5.37 (t, J=6.7 Hz,1H), 4.44 (dd, J=3.2, 6.64 Hz, 1H), 4.20-4.09 (m, 3H), 3.74 (dq, J=2.1,11.5 Hz, 1H), 3.34 (dddd, J=2.7, 2.7, 7.6, 7.6 Hz, 1H), 2.71 (s, 3H),2.41-2.25 (m, 5H), 2.02 (s, 3H), 1.68 (s, 3H) 1.25 (s, 3H), 1.16 (s,3H), 1.13 (d, J=7.1 Hz, 3H), 1.06 (d, J=6.9 Hz, 3H), 0.98 (obscured m,2H), 0.94 (t, J=8.1, 9H) 0.92 (s, 9H), 0.88 (s, 9H), 0.59 (q, J=7.9,9H), 0.10 (s, 3H), 0.07 (s, 6H), 0.04 (s, 9H), 0.03 (s, 3H); ¹³C NMR(CDCl₃, 75 MHz) δ 219.2, 172.6, 164.7, 153.6, 142.9, 132.8, 122.4,119.1, 115.4, 83.5, 80.6, 78.8, 76.4, 73.9, 63.9, 54.1, 41.1, 36.0,33.0, 30.1, 26.4, 24.1, 19.6, 19.5, 19.4, 19.1, 18.9, 18.7, 18.6, 17.7,16.1, 14.4, 7.3, 5.22, −1.1, −−2.9, −3.5, −4.0, −4.3; HRMS (FAB)calculated for C₅₀H₉₄NO₆SSi₄ (M+H⁺) 948.58790, found 948.59258.

Example 41

[0156] This example describes the synthesis of compound 120. To astirred solution of dienyne 118 (8.0 mg, 8.4 μmol) and powderedmolecular sieves (100 mg) in THF (1.5 mL) at 0° C. was addedtetra-n-butylammonium fluoride (6.0 mg, 25 μmol). After 1 hour, themixture was filtered through glass wool, and aqueous citric acid (pH 5,3.0 mL) was added to the filtrate, which was extracted with Et₂O. Thedried (MgSO₄) extract was concentrated in vacuo and the residue waspurified by flash chromatography on silica gel, eluting with 4%MeOH/CH₂Cl₂, to give 120 (8.2 mg, quantitative) as a colorless oil:[α]_(D) ²³−0.17 (c 0.82, CHCl₃); IR (neat) 3338, 2954, 2929, 2856, 1713cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 6.96 (s, 1H), 6.58, (s, 1H), 5.50 (t,J=6.7 Hz, 1H), 4.46 (dd, J=2.1, 4.7 Hz, 1H), 4.20 (t, J=4.7H), 3.80 (dd,J=1.1, 5.6 Hz, 1H), 3.34 (dddd, J=5.5, 5.5, 5.5, 10.9 Hz, 1H), 2.9 (s,1H), 2.73 (s, 3H), 2.58-2.25 (m, 5H), 2.05 (s, 3H), 1.72 (s, 3H) 1.24(s, 3H), 1.20 (s, 3H), 1.15 (d, J=5.4 Hz, 3H), 1.10 (d, J=5.2 Hz, 3H),0.93 (s, 9H), 0.90 (s, 9H), 0.11 (s, 3H), 0.09 (s, 9H); ¹³C NMR (75 MHz,CDCl₃) δ 219.1, 175.4, 165.4, 153.0, 142.2, 134.6, 121.2, 119.3, 115.8,84.1, 80.4, 76.4, 73.6, 54.4, 46.7, 40.4, 34.7, 33.0, 30.1, 29.6, 26.5,26.4, 23.9, 19.2, 19.2, 18.9, 18.6, 16.9 16.4, 14.9, −2.94, −3.5, −3.6,−4.2; HRMS (FAB) calculated for C₃₉H₆₈NO₆SSi₂ (M+H⁺) 734.43082, found734.42877.

Example 42

[0157] This example describes the synthesis of compound 122. To astirred solution of seco acid 120 (8.8 mg, 12.0 μmol) in THF (0.2 mL) at0° C. was added Et₃N (2.9 PL, 21 μmol) followed by2,4,6-trichlorobenzoyl chloride (2.2 μL, 14 μmol). After 45 minutes, themixture was diluted with THF (0.16 mL) and toluene (0.26 mL), and wasadded via syringe pump to a stirred solution of DMAP (2.4 mg, 20 μmol)in toluene (2.8 mL) at 75° C. during 3.5 h. After an additional 1 h, thesolution was allowed to cool to room temperature, diluted with EtOAc,washed with saturated aqueous NH₄Cl (10 mL), and extracted with EtOAc(4×20 mL). The dried (Mg₂SO₄) extract was concentrated in vacuo and theresidue was purified by chromatography on silica gel, eluting with 5%EtOAc/hexanes, to give macrolactone 122(4.1 mg, 47%) as a colorless oil:[α]D²³ 11.9 (c 0.41, CHCl₃); IR (neat) 2925, 2854, 1739, 1702, 1463cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 6.94 (s, 3H), 6.55 (s, 3H), 5.70 (t,J=6.2, 1H), 5.33 (dd, J=2.6, 11.3 1H), 4.64 (dd, J=2.5, 8.2, 1H), 3.94(dd, J=2.5, 8.1 1H), 3.26 (dq, J=7.0, 14.9 Hz, 1H), 2.71 (s, 3H),2.70-2.35 (m, 5H), 2.15 (s, 3H), 1.66 (s, 3H), 1.16 (d, J=7.1 Hz, 3H),1.14 (s, 3H), 1.14 (s, 3H), 1.13 (obscured d, 1H), 0.91 (s, 9H), 0.86(s, 9H), 0.13 (s, 3H), 0.10 (s, 3H), 0.08 (s, 3H), 0.07 (s, 3H); ¹³C NMR(100 MHz, CDCl₃) δ 215.7, 170.9, 165.1, 153.1, 139.0, 137.8, 132.9,121.5, 120.1, 116.7, 85.5, 80.3, 79.8, 77.6, 76.4, 73.3, 55.2, 44.4,42.5, 33.1, 32.5, 30.1, 29.0, 26.4, 26.4, 19.8, 19.7, 18.7, 18.5, 18.0,17.4, 15.2, −2.9, −3.3, −3.8, −4.1; HRMS (FAB) calculated forC₃₉H₆₆NO₅SSi₂ (M+H⁺) 716.42003, found 716.42093.

Example 43

[0158] This example describes the synthesis of compound 124. To astirred solution of 122 (4.1 mg, 5.7 μmol) in CH₂Cl₂ (200 μL) at 0° C.was added trifluoroacetic acid (100 mL). After 10 hours, the mixture wasconcentrated in vacuo, and the residue was purified by chromatography onsilica gel, eluting with 20-50% EtOAc/hexanes, to give 124 (2.4 mg, 19μmol, 86%) as a colorless waxy solid: [α]_(D) ²³−37.9 (c 0.24, CHCl₃);IR (neat) 3480, 2925, 1731, 1692 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 6.98(s, 1H), 6.56 (s, 1H), 5.49 (t, J=7.9, 1H), 5.38 (dd, J=3.1, 9.9, 1H),4.43 (dd, J=5.6, 5.6, 1H), 3.60 (dd, J=8.2, 8.2, 1H), 3.26 (dddd, J=6.7,6.7, 6.8, 15.5 Hz, 1H), 2.71 (s, 3H), 2.65-2.35 (m, 5H), 2.11 (s, 3H),1.74 (s, 3H), 1.27 (d, J=6.9, 3H), 1.25 (d, J=7.1, 3H) 1.21, (s, 3H),1.09 (s, 3H); ¹³C NMR (100 MHz, CDCl₃) δ 218.5, 171.1, 165.3, 152.6,137.8, 134.5, 121.3, 120.4, 116.8, 82.7, 82.3, 79.2, 77.6, 76.6, 72.1,53.5, 47.4, 39.8, 32.7, 31.9, 29.5, 22.2, 19.6, 19.4, 18.9, 17.0, 16.8,15.8; HRMS (FAB) calculated for C₂₇H₃₈NO₅S (M+H⁺) 488.24676, found488.24707.

Example 44

[0159] This example describes the synthesis of compound 81. To a stirredsolution of the crude aldehyde 79 in t-BuOH (0.88 mL) and H₂O (0.83 mL)was added 2-methyl-2-butene (0.16 mL) followed sequentially by NaH₂PO₄(55.7 mg, 0.46 mmol) and NaClO₂(27.1 mg, 0.30 mmol). After 1 hour, thereaction was quenched with saturated aqueous NaCl (1.5 mL), and themixture was extracted with Et₂O (4×5 mL). The dried (MgSO₄) extract wasconcentrated in vacuo and the residue was purified by chromatography onsilica gel, eluting with 20% EtOAc in hexanes to give acid 81 (38 mg0.061 mmol, 93%) as a colorless oil: [α]D²³-26.8 (c 1.20, CHCl₃); IR(neat) 2400-3400, 1735, 1722 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 4.40 (dd,J=3.6, 6.9 Hz, 11H), 4.15 (m, 3H), 4.03 (dd, J=2.2, 7.9 Hz, 11H), 3.36(dq, J=7.3, 7.3 Hz, 11H), 2.45 (td, J=2.2, 7.4 Hz, 1H), 2.37 (d, J=3.4Hz, 1H), 2.26 (dd, J=7.0, 16.1 Hz, 1H), 1.23 (d, J=7.1 Hz, 3H) 1.22 (s,3H), 1.14 (s, 3H), 1.11 (d, J=6.9 Hz, 3H) 0.98 (m, 3H), 0.93 (s, 9H),0.87 (s, 9H), 0.15 (s, 3H), 0.14 (s, 3H), 0.10 (s, 3H), 0.04 (s, 9H),0.02 (s, 3H); ¹³C NMR (75 MHz, CDCl₃) δ 218.2, 177.4, 172.7, 76.6, 73.9,63.2, 54.2, 46.8, 45.2, 40.9, 30.1, 26.4, 26.4, 24.1, 19.3, 18.7, 18.6,17.6, 15.9, 15.6, −1.1, −3.2, −3.5, −4.0, −4.2; HRMS (CI) calculated forC₃₀H63O₇Si₃ 619.38750; found 619.38817.

Example 45

[0160] This example describes the synthesis of compound 124. To astirred solution of 81 (30.0 mg, 0.048 mmol) in THF (0.25 mL) was added104 (20.6 mg, 0.073 mmol) and triphenylphosphine (31.4 mg, 0.12 mmol).The solution was cooled to 0° C. and diethyl azodicarboxylate (0.017 mL,0.11 mmol) was added. After 4 hours, the reaction was quenched withsaturated aqueous NH₁₄Cl, and the solution was extracted with Et₂O. Theextract was concentrated in vacuo, and the residue was purified bychromatography on silica gel, eluting with 10% Et₂O/petroleum ether, togive ester 124 (30 mg, 65%) as a colorless oil: [α]D²³-20.7 (c 1.50,CHCl₃); IR (neat) 2954, 1735, 1251 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 6.92(s, 1H), 6.46 (s, 1H), 5.42 (t, J=7.3 Hz, 1H), 4.61 (d, J=12.1 Hz, 1H),4.51 (d, J=12.1 Hz, 1H), 4.41 (dd, J=3.0, 6.6 Hz, 1H), 4.13 (m, 3H),3.47 (dq, J=7.1, 7.1 Hz, 1H), 2.71 (s, 3H), 2.47-2.13 (m, 5H) 1.99 (s,3H), 1.75 (s, 3H), 1.24 (s, 3H), 1.15 (d, J=7.1 Hz, 3H), 1.12 (s, 3H),1.04 (d, J=6.9 Hz, 3H), 0.98 (m, 3H), 0.92 (t, J=7.7, 9H), 0.85 (s,18H), 0.57 (q, J=7.9 Hz, 6H), 0.09 (s, 3H), 0.07 (s, 3H), 0.04 (s, 3H),0.03 (s, 9H), 0.02 (s, 3H); ¹³C NMR (75 MHz, CDCl₃) δ 218.2, 173.7,172.6, 164.9, 153.2, 142.6, 131.9, 127.2, 119.1, 115.5, 78.5, 76.3,74.2, 63.7, 63.1, 53.9, 45.6, 40.9, 35.5, 26.4, 24.2, 22.1, 17.7, 15.5,15.1, 14.4, 7.2, 5.2, −1.1, −3.5, −4.0, −4.2; HRMS (CI) calculated forC₄₉H₉₄O₈SSi₄ 968.57773; found 968.57748.

Example 46

[0161] This example describes the synthesis of compound 130. To astirred solution of 124 (30 mg, 31 μmol) and powdered molecular sieves(100 mg) in THF (5.0 mL) at 0 C was added tetra-n-butylammonium fluoride(24.0 mg, 96 μmol). After 2 hours, the mixture was filtered throughglass wool, and aqueous citric acid (pH 5, 5 mL) was added to thefiltrate, which was extracted with Et₂O. The dried (MgSO₄) extract wasconcentrated in vacuo and the residue was purified by flashchromatography on silica gel, eluting with 3% MeOH/CH₂Cl₂, to give secoacid 130(15.0 mg, 66%) as a colorless oil: [α]_(D) ²³−26.9 (c 0.75,CHCl₃); IR (neat) 3107, 2929, 1716, 1422 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ6.96 (s, 1H), 6.64 (s, 1H), 5.46 (t, J=7.3 Hz, 1H), 4.69 (d, J=11.8 Hz,1H), 4.47 (d, J=11.8 Hz, 1H), 4.42 (dd, J=3.6, 6.3 Hz, 1H), 4.17 (t,J=6.8 Hz, 1H), 4.09 (dd, J=2.5, 7.7 Hz, 1H), 3.42 (dq, J=7.4, 7.4 Hz,1H), 2.72 (s, 3H), 2.56-2.19 (m, 5H) 2.00 (s, 3H), 1.80 (s, 3H), 1.23(s, 3H), 1.17 (s, 3H), 1.16 (d, J=7.1 Hz, 3H), 1.08 (d, J=6.9 Hz, 3H),0.88 (s, 9H), 0.87 (s, 9H), 0.10 (s, 3H), 0.10 (s, 3H), 0.08 (s, 3H),0.05 (s, 3H); ¹³C NMR (75 MHz, CDCl₃) δ 218.4, 175.3, 173.8, 165.6,152.8, 142.4, 133.5, 126.7, 118.9, 115.6, 76.1, 73.8, 63.8, 54.3, 45.9,45.7, 40.6, 34.4, 26.4, 24.2, 22.2, 19.4, 19.2, 18.7, 16.1, 15.3, 13.8,−3.6, −3.7, −3.8, −4.2; HRMS (CI) calculated for C₃₈H₆₈O₈NSSi₂754.42042; found 754.42119.

Example 47

[0162] This example describes the synthesis of compound 132. To astirred solution of 130 (15.0 mg, 20.0 μmol) in THF (0.4 mL) at 0° C.was added Et₃N (4.9 μL, 35 μmol) followed by 2,4,6-trichlorobenzoylchloride (3.6 μL, 23 μmol). After 45 minutes, the mixture was dilutedwith THF (0.3 mL) and toluene (0.4 mL), and was added via syringe pumpto a stirred solution of DMAP (4.2 mg, 34 μmol) in toluene (4.6 mL) at75° C. during 4 hours. After an additional 1 hour, the solution wasallowed to cool to room temperature, diluted with EtOAc, washed withsaturated aqueous NH₄Cl (20 mL), and extracted with EtOAc (4×40 mL). Thedried (Mg₂SO₄) extract was concentrated in vacuo and the residue waspurified by chromatography on silica gel, eluting with 5% EtOAc/hexanes,to give 132 (9.0 mg, 60%) as a colorless oil: [α]_(D) ²³−36.6 (c 0.45,CHCl₃); IR (neat) 2927, 1741, 1471 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 6.96(s, 1H), 6.57 (s, 11H), 5.44 (dd, J=5.7, 11.8 Hz, 11H), 5.34 (dd, J=3.3,8.8 Hz, 1H) 4.83 (d, J=11.5 Hz, 1H), 4.46 (m, 2H), 4.02 (dd, J=1.6, 8.7Hz, 1H), 3.34 (dq, J=7.4, 7.4 Hz, 1H), 2.82 (m, 1H), 2.71 (s, 3H), 2.56(m, 3H), 2.28 (m, 1H) 2.15 (s, 3H), 1.74 (s, 3H), 1.23 (d, J=7.4 Hz,3H), 1.20 (d, J=7.1 Hz, 3H), 1.16 (s, 3H), 1.09 (s, 3H), 0.90 (s, 9H),0.85 (s, 9H), 0.15 (s, 3H), 0.07 (s, 3H), 0.06 (s, 3H), 0.02 (s, 3H);¹³C NMR (75 MHz, CDCl₃) δ 217.0, 173.4, 170.8, 165.1, 152.8, 136.6,133.7, 126.7, 121.3, 116.8, 79.2, 76.6, 73.7, 62.6, 54.2, 48.3, 45.6,41.9, 33.3, 26.5, 25.1, 22.3, 20.4, 19.7, 18.7, 18.6, 17.4, 15.2, −3.4,−3.5, −3.7, −4.2; HRMS (CI) calculated for C₃₈H₆₆O₇NSSi₂ 736.40986;found 736.40850.

Example 48

[0163] This example describes the synthesis of compound 134. To astirred solution of 78 (4.5 mg, 6 μmol) in CH₂Cl₂ (200 μL) at 0° C. wasadded trifluoroacetic acid (100 μL). After 8 hours, the mixture wasconcentrated in vacuo, and the residue was purified by chromatography onsilica gel, eluting with 20-2% MeOH/CH₂Cl₂, to give 79 (3 mg, 6 μmol,99%) as a colorless oil: [α]D²³ 40.0 (c 0.15, CHCl₃); IR (neat) 3503,2924, 1732, 1458 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 7.00 (s, 1H), 6.60 (s,1H), 5.45 (dd, J=6.0, 11.0 Hz, 1H), 5.28 (d, J=9.6 Hz, 1H) 5.02 (d,J=11.2 Hz, 1H), 4.21 (d, J=12.3 Hz, 1H), 4.02 (m, 1H), 3.77 (m, 1H),3.46 (m, 1H), 3.23 (dq, J=6.8, 6.8 Hz, 1H), 2.74 (s, 3H), 2.67 (m, 3H),2.45 (m, 2H), 2.24 (m, 1H), 2.11 (s, 3H), 1.78 (s, 3H), 1.38 (d, J=7.1Hz, 3H), 1.31 (s, 3H) 1.27 (d, J=6.8 Hz, 3H), 1.10 (s, 3H); ¹³C NMR (75MHz, CDCl₃) δ 218.9, 177.2, 170.9, 165.4, 152.8, 137.9, 133.6, 126.1,120.7, 116.9, 78.9, 75.6, 73.3, 63.9, 52.7, 47.9, 41.7, 39.0, 32.7,22.3, 21.9, 21.8, 19.6, 16.8, 16.5, 15.7; HRMS (CI) calculated forC₂₆H₃₈O₇NS 508.23690; found 508.23641.

[0164] The present method has been described in accordance with workingembodiments; however, it will be understood that certain modificationsmay be made thereto without departing from the method. We claim as ourinvention the disclosed embodiments and all such modifications andequivalents as come within the true spirit and scope of the followingclaims.

We claim:
 1. A compound according to the formula:

where G is selected from the group consisting of

R substituents independently are H, lower alkyl, or a protecting group;R₁ is an aryl group; R₂ substituents independently are selected from thegroup consisting of H and lower alkyl groups; Z is selected from thegroup consisting of the halogens and —CN; M is selected from the groupconsisting of O and NR₃; R₃ is selected from the group consisting of H,lower alkyl, R₄CO, R₄OCO, and R₄SO₂; R₄ is selected from the groupconsisting of H, lower alkyl, and aryl; T is selected from the groupconsisting of CH₂, CO, HCOH and protected derivatives thereof; W is H orOR; and X and Y independently are selected from the group consisting ofO, NH, S, CO, and C.
 2. The compound according to claim 1 where X and Ycomprise a carboxylic acid derivative.
 3. The compound according toclaim 1 where X and Y mutually comprise an ester bond.
 4. The compoundaccording to claim 1 where X is C═O and Y is O.
 5. The compoundaccording to claim 4 where R₁ comprises a heterocycle.
 6. The compoundaccording to claim 4 where R₁ comprises an aryl group.
 7. The compoundaccording to claim 8 where R₁ has the formula

where X and Y independently are selected from the group consisting of O,N, and S, and R₆ is selected from the group consisting of H and loweralkyl.
 8. The compound according to claim 1 where X and Y mutuallycomprise a triple bond.
 9. A compound according to the formula:

where R substituents independently are H, lower alkyl, or a protectinggroup, R₁ is an aryl group, R₂ and R₃ independently are selected fromthe group consisting of H and lower alkyl groups, R₄ substituentsindependently are selected from the group consisting of lower alkylgroups, and X and Y independently are selected from the group consistingof O, NH, S, CO, and C.
 10. The compound according to claim 9 where Xand Y mutually comprise an ester bond.
 11. The compound according toclaim 10 where the compound has the formula


12. The compound according to claim 9 where the compound has the formula


13. The compound according to claim 9 where the compound has the formula


14. A compound according to the formula

where R substituents independently are H, lower alkyl, or a protectinggroup, R₁ is an aryl group, R₂ and R₃ independently are selected fromthe group consisting of H and lower alkyl groups, R₄ substituentsindependently are selected from the group consisting of lower alkylgroups, and X and Y independently are selected from the group consistingof O, NH, S, CO, and C.
 15. The compound according to claim 14 where Xand Y mutually comprise an ester bond.
 16. The compound according toclaim 15 where R and R₂ are H, R₃ and R₄, are methyl.
 17. The compoundaccording to claim 16 where R₁ has the formula

where X and Y independently are selected from the group consisting of O,N, and S, and R₆ is selected from the group consisting of H and loweralkyl.
 18. The compound according to claim 14 where R₁ is


19. A compound according to the formula:

where R substituents independently are H, lower alkyl, or a protectinggroup, R₁ is an aryl group, R₂ and R₃ independently are selected fromthe group consisting of H and lower alkyl groups, R₄ substituentsindependently are selected from the group consisting of lower alkylgroups, and X and Y independently are selected from the group consistingof O, NH, S, CO, and C.
 20. The compound according to claim 19 where Xand Y comprise an ester bond.
 21. The compound according to claim 19where the compound has the formula


22. A compound according to the formula:

where R substituents independently are H, lower alkyl, or a protectinggroup, R₁ is an aryl group, R₂ and R₃ independently are selected fromthe group consisting of H and lower alkyl groups, R₄ substituentsindependently are selected from the group consisting of lower alkylgroups, and X is selected from the group consisting of O, NH, S, and C.23. The compound according to claim 22 where R₁ has the formula

where X and Y independently are selected from the group consisting of O,N, and S, and R₆ is selected from the group consisting of H and loweralkyl.
 24. A method, comprising: providing a first compound according tothe formula

where R is H or a protecting group, R₁ is an aryl group, and X isselected from the group consisting of OH, NH2, SH, protected derivativesthereof, and halogens; providing a second compound according to theformula

where R is H or a protecting group, R₄ substituents independently areselected from the group consisting of lower alkyl groups, Y is selectedfrom the group consisting of alkynes, alkenes, and carboxylic acidderivatives; and coupling the first and second compounds.
 25. The methodaccording to claim 24 where coupling comprises a transitionmetal-mediated coupling reaction.
 26. The method according to claim 24where coupling comprises an esterification reaction.
 27. The methodaccording to claim 24 where coupling comprises an amide bond-formingreaction.
 28. A method, comprising: providing a compound according tothe formula

performing a macrolactonization reaction.
 29. The method according toclaim 28 where the compound has the formula


30. A method of treating a cancer, comprising: providing an effectiveamount of a compound according to the formula

where G is selected from the group consisting of

R substituents independently are H, lower alkyl, or a protecting group;R₁ is an aryl group; R₂ substituents independently are selected from thegroup consisting of H and lower alkyl groups; Z is selected from thegroup consisting of the halogens and —CN; M is selected from the groupconsisting of O and NR₃; R₃ is selected from the group consisting of H,lower alkyl, R₄CO, R₄OCO, and R₄SO₂; R₄ is selected from the groupconsisting of H, lower alkyl, and aryl; T is selected from the groupconsisting of CH₂, CO, HCOH and protected derivatives thereof; W is H orOR; and X and Y independently are selected from the group consisting ofO, NH, S, CO, and C.
 31. The method according to claim 30 where thecancer is responsive to microtubule stabilization.
 32. The methodaccording to claim 30 where the cancer is selected from the groupconsisting of breast cancer, ovarian cancer, colon cancer, head and neckcancer, lung cancer, melanoma, brain cancer, germ cell cancer,urothelial cancer, esophageal cancer, non-Hodgkin's lymphoma, multiplemyeloma, prostrate cancer, bladder cancer, pancreatic cancer, renalcancer, leukemia, and Karposi's sarcoma.
 33. The method according toclaim 30 where the cancer is a paclitaxel-resistant cancer.
 34. A methodfor making an epothilone or epothilone analog, comprising: making aprecursor compound by coupling a first compound having the formula

where R is H or a protecting group and X is a functional groupequivalent to a carbanion at a terminal carbon of the first compound,with a second compound having the formula

where R₂ is H or lower alkyl, R₃ is H or a protecting group, and Y is anelectrophilic group capable of reacting with and coupling to theterminal carbon of the first compound; and converting the precursorcompound into the epothilone or epothilone analog.
 35. The methodaccording to claim 34 where X of Formula 4 is PPH₃+.
 36. The methodaccording to claim 34 where X of Formula 4 is a sulfone.
 37. The methodaccording to claim 34 where Y of Formula 5 is CHO.